Steve Young at the Pinball Resource has them I believe.

Very Nice! Having a nice playfield like that is a huge help. I'm waiting on a CPR playfield as my playfield was completely blown out.
I'm in the process of completely rebuilding/restoring mine still, though its on hold while I'm moving to a new house.

Your playfield is in Much better shape than mine was. I'm waiting on a CPR playfield for mine as it was a lost cause to attempt to repair.
Pretty sure HSA is closed at this point, so you might have to look to another playfield restorer if you want to save that one.
I had to build an entire new cab for it as mine was dry rotted and delaminating all over. Cabinet wood, Pinball pimp stencils, new coin door skin, new Rectifier board, new stainless rails, new glass, coin door lock, shooter rod, coin door bolts, it adds up quick and that's just for the cabinet.
My biggest heads up for you is to be prepared to re-pin all the connectors and replace all board headers in addition to having to replace many of the lamp sockets. Connectors will either be loose or corroded and the lamp sockets will be no better off.
Good luck and let us know how it goes!

No problem. I love to see games getting restored.
Let us know how your restoration goes. I'm sure i'll need some ideas for mine as well!

To remove the front glass, open the backbox, on the door that swings out near the top, there are two metal tabs you have to pull back.
They block the front glass from lifting, once you pull them back you can lift the front glass up and out.

For mine, I had to build a whole new lower cab but I was able to save the backbox outer door frame, lamp insert and *most* of the back box. I had to replace the back panel as it had moisture damage and was swollen. The rest of the backbox was ok, just needed lots of sanding and filling to get it smooth again.

The MPU that came with mine was beyond destroyed due to battery leakage. It was missing numerous traces and had damaged through holes as well. I built a new one from scratch using a two-bits board I got on eBay (they are still listed I believe, $50 for a blank pcb). The rest of the parts were sourced from Ed at GPE and a few from Digikey\Marcos\Mouser. I wanted to keep it as original looking as I could (just felt like keeping it that way on this game) and i was looking for a good solder project for a weekend.
If you wanted a new board with less work involved, I would look at a replacement board from barakandl at nvram.weebly.com .He has several other boards for this era of game as well (MPU, SDB, Lamp, Rectifier, -51 sound, etc..). You can also go with Alltek if you choose.

Nice grab there. That MPU seems to be in pretty good shape, though please cut off that battery ASAP. You can replace it with an nvram to be done with batteries for good. You will likely need to replace many of the sockets, especially if they are of the scanbe type. Those things go bad and then nothing makes contact correctly.
The lamp driver looks to be in good shape as well. Looks like a few components have been replaced at some point. Thankfully there isn't much work to do to those other than replacing the headers.

There are quite a few beat up games out there that I'm sure you could fine a populated playfield. Pretty sure I saw one in a group someone had for sale a few weeks back. There aren't that many parts to the game that are unique either. Only harder parts to acquire would likely be the apron, drop target banks, horseshoe ball guide, transformer and backglasses. I don't think it will be too bad to source boards, playfield, plastics, posts, etc... as all of them have been remade as of late.
Technically I think I have a spare horsehoe ball guide as Vid1900 made me a new one a year or so back that is going on SI once i get a new pf.
Let me know if you need that and i can send it your way. Good luck on the scratch build.

I might be able to help with the playfield rails fairly soon as well. I need to get ahold of Reese Rails and see if he can use my old rails to make a template for some new ones. I'll have a spare rail set and horseshoe ball guide once I can get a new PF to start populating.

Yea that -49 rectifier board looks to be in pretty good shape. All you'd really need to replace would be header pins, fuse clips and the bridge rectifiers. I would also replace CR1 - CR4 with matching diodes, as yours appear to be mismatched. You *can* replace the varo 712E devices with a bridge rectifier if you'd like as well. I left them on mine as they worked just fine and the load was a bit lower since LEDs will be used for everything but the chase lights, so less heat and stress on those.
As for that MPU, I would call that dead. The amount of work to get it de-populated, cleaned, check all the traces for breaks, rebuild and test just isn't worth it in my book. At least you can salvage some of the chips and Roms from that board. But you have a 2nd MPU coming that is in much better shape, so it all works out.

Looks good, one of the better -35s i've seen in a while.

If you have the skills to accomplish all of that and you feel that the final product is what you are wanting, then go for it. Its very much up to personal preference and based on what skills you have.
My SI restore started with a game in horrid shape. Plywood de-lamination, rust, corrosion, outright broken parts, mouse nests and mangled wiring, so it was pretty bad. I was able to save *most* of the head, but the rest of the cabinet was completely replaced. I used Pinball Pimp stencils and had no issues. I wanted to learn the process and attempt to pick up some new skills as part of my restore. Here are some photos for reference. I plan to make a thread of my own once I get a new CPR pf and can finally get this project finished.

Before:
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During:
20170501_204657 (resized).jpg
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MVIMG_20171216_164319 (resized).jpg
MVIMG_20171218_173312 (resized).jpg
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MVIMG_20171227_173437 (resized).jpg
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MVIMG_20171228_203333 (resized).jpg

And After:
IMG_20180118_203806 (resized).jpg
IMG_20180128_203715 (resized).jpg

Yea, mine was routed for then left in a garage until I got it basically for free.

The stenciling wasn't that difficult. SI has pretty complex artwork so the only part I was nervous about was peeling the stencil off after I painted. Here was my way of doing it:
1- lay stencil down
2- I laid down multiple light paint layers immediately after each other until it was covered to my liking
3- Wait 10-15min, then start peeling the stencil up
4- wore gloves to peel the stencil as you Will get covered in paint, peeled slowly by pulling straight up or close to it, be careful with the intricate art pieces so they don't tear off the stencil, I had some small junk needle nose pliers ready in case I needed to grab a few small pieces that tore off
5 - left it for a week before i did the next layer (As the layers are rather thick, i wanted to give it enough time to dry completely, also i did this in the winter and it was a bit cooler than i'd prefer in the basement so i had a small heater running in my make-shift paint tent to keep it ~70°.)

Long story short, multiple light layers back to back over several minutes per stencil. I had no issues with paint tearing or running or anything else. The worst thing I did was a drop part of a peeled stencil on the cab as I was peeling. Thankfully, I was able to just wipe it up in the area it touched, so no issues in the end. This was all done with Rustoleum 2X spray paint. Here are the colors I used..
IMG_20190928_173325 (resized).jpg
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For the cabinet, I broke the old cabinet down and used it as a template for the new one.
Table saw, router, a sharp pencil and some good wood glue. I got the wood from a local cabinet shop as they tend to have a nice selection of wood available and let me have some scrap they had as well for smaller stuff in the cabinet.
20170120_203345 (resized).jpg

Hopefully that was helpful, let me know if you had any other questions. CPR is apparently CNCing the new SI playfields right now, so hopefully I'll get my new pf before too long and I'll start a new thread in the restoration section about this whole process.

I would say that you could do it. There are a ton of resources for anything pin related on Pinside and on Pinwiki. Those two sites are where I researched the vast majority of restoration tools, techniques, vendors and parts.

Not 100% sure on the alltek, but 6 flashes means missing +43v. Check your SDB as I think the +43v comes from there and not directly from the Rectifier board.

make sure the +43v is making it to the MPU board. Sounds like a possible connector issue.

Check the Rectifier board to make sure you are getting the correct voltages. After that go after the connectors and replace the pins. The GI pins are always burnt and likely need replacing. Remember to replace the 0.156 with trifurcon pins

Correction, it appears that the +43 does come from the rectifier board. there is some info here https://www.pinwiki.com/wiki/index.php?title=Bally/Stern#Seventh_flash about getting the 7th flash. Again, this is not for an Alltek but for the factory -35 board.

Wiring looks correct compared to my SI. Same wires in the same locations.
Are you sure the driver is ok for that pair?
Schematic is showing that light pair as 82. Which is pin7 on the Aux J3 connector. Points me to Q20 (MCR106 i believe).
Should be just to the left of J3. Might want to give that one a check.

If that doesn't work. I would trace the wire back and make sure its not a connector issue.

FYI, it appears that CPR has Space Invaders playfields back in stock
CPR_SI_FB (resized).png

My plug is the same.
I'm no pro at diagnosing the Bally boardset, but from what you've said, the only things that really remain are checking the MPU, checking the wiring, checking fuses or looking for broken wires.

Glad you got it working again!

I have an ongoing restoration of my Space Invaders in another thread https://pinside.com/pinball/forum/topic/space-invaders-restoration-bringing-back-a-hunk-of-junk. Mine isn't finished yet (soldering the harness back to the playfield currently), but i did build a new cab from scratch and used those exact stencils to make mine.

You likely wont be able to get them anywhere unless you find someone parting out a pin.
You probably will need to make some of your own. Vid1900 has a good guide for that
https://pinside.com/pinball/forum/topic/making-new-ball-guides-from-scratch-vids-guide
Its not that hard to do, I had to make 3-4 of them for my Xenon.

A few suggestions from rebuilding my SI from scratch over the past few years. Apologies in advance, but this won't be that organized...
Here is my thread if you want to see anything else I did https://pinside.com/pinball/forum/topic/space-invaders-restoration-bringing-back-a-hunk-of-junk

-Use LEDs from Comet or Cointaker. Just better quality overall and they have better light. I tried Pinballlife, Marcos and Comet in mine and Comet won.
-remember to either modify the lamp driver or buy the adapter boards to use LEDs with -35 era bally pins. The extended board does not need the adapters, at least mine did not. They are available if you have issues.
-You will have bad lamp sockets, plan to buy some. They aren't cheap unless you buy in bulk. even then...
-likely will be bad caps on several of the switches. Just replace them all.
-There are 4 flippers on the game, so you will need 2 kits. The upper flippers also have an extra switch for the noise you can (optionally) enable. You have to DIY that or you can get the flipper kit from PBR who will get you exactly what you need.
-check the flipper bats for cracks. also check to see how the metal is where the screw digs it. some are pretty trashed.
-replace all the sleeves in the game. Flippers, drop targets, pop bumpers, kickers, knocker
-check the drop targets as those can break or have issues. Mine had to be replaced.
-pop bumper caps are generally burnt bad on SI. I had to replace mine with NOS ones I was able to source. Beware some crappy ones that show up on feebay and other such locations.
-I sourced my posts from PBR, I believe it was 8 short and 32 tall
-make sure you have enough metal nuts for the plastics. I was missing many and they are in short supply. I ended up going with the nylon ones. Not original, but looks good and is easy to source.
-I use a pindoc Pro rotisserie. I just prime/painted it myself. Works great.
-make sure the boards are all built up and working correctly. SDB ground mods are a bit of a must with this game as is new fuse holders for the rectifier board. Check all the sockets on the boards as most of them will be crap. Headers, headers headers. Replace them all along with the pins.
-check the shooter bushing, I believe its a C-934, as it will likely need to be replaced. Marcos had them the last time I checked.
-I ended up needing alot of spare hardware as some stuff was just too corroded or broken or worn to be reused. I got a big bag of everything and it very much helped during the rebuild.

Good Luck and let us know how it goes!

This forum post covers the adapters for the lamp driver board and it covers more of a DIY approach if you are into that. The big reason they are needed is to prevent flickering. https://pinside.com/pinball/forum/topic/classic-ballystern-led-adapter-kit-review
Here is another guide for most of the boards that are in SI, the important ones are the rectifier, SDB and MPU. https://pinside.com/pinball/forum/topic/vids-guide-quick-bally-driver-board-repair-bulletproofing

both of these are posts that I used for my rebuild and they helped immensely

You are missing a switch for that new flipper.
Both the upper flippers on space invaders have both the standard EOS switch and a scoring switch that is used to trigger a sound (if enabled).

What you should be able to do is use the new EOS switch and stack the old scoring switch on top of it and use the old screws (so that they're long enough) to screw it all in. Make sure the screw does NOT hit the coil when screwed in. Just make sure that when the flipper is fully extended, the EOS switch should be open and the scoring switch should be closed. Vid1900 has a good rebuild thread you can reference for flipper rebuilds.
If you want a new scoring switch, I used pinball resource for mine and they worked great. That being said, I'm sure Marcos or pinballlife both have available options as well.

Two things for you on that one...
1) Space Invaders has two backglasses, an inner backglass with the mirroring and artwork and an outer backglass that is smoked with no other artwork (the infinity lights are sandwiched in-between).
2) I don't think anyone has repro'd any smoked backglasses, at least not that I've heard of.

I don't think anyone is producing repro backglasses (inner or outer) for this title currently, but BGResto does to restorations on the inner glass.
That being said, you'd probably have to find a game with both glasses and get the inner restored if its in bad shape. Unless, that is, you can get lucky and find some in great shape.
All that being said, they made a ton of this game, so I would think you could find a pair of glasses if you really tried.

Not that I'm aware of.