in gold ball thread I'd suggested looking for an 11-12" (edit: waay too large!) clear, round bottom inside polycarbonate bowl to trim to size..
poly being much-much tougher than plexi. an RC hobby shop or online supplier will have etching paint for polycarbonate RC car bodies. if I couldnt find a suitable bowl anywhere, then fiberglass cloth and epoxy resin to lay one up by hand, epoxyglass is pretty shatterproof, not too hard to work with to make almost anything.

_{Post edited by zizzlemeplease: learned later this dish is about 61mm radius}

thinner poly might not have the sheer crush strength as that model (impressive btw) but poly sure can take impact abuse. I did a quick search for poly bowls other day, but not long enough to find a suitable round bottomed candidate for this PF item.. I'm curious, what the radius if it were a complete sphere? it'd be helpful for ID'ing an off the shelf bowl thats close enough. (glad its not a parabola, that'd be a really tough find!)

a search for "clear polycarbonate DOME" seems to get more appropriate results, some for CCTV cameras look pretty close if theyre trimmed. http://www.cleardome.com/smalldomes.htm has lots of sizes and bottom of list links for larger than 8" diameter. http://www.foodservicedirect.com/product.cfm/p/1938872/Polycarbonate-Clear-Round-Pebbled-Bowl-0.6-Quart.htm cant tell if its close to size but the price sure cheep, saw one at that site was stainless steel as an ice cream dish.

I cant really tell the size of whats needing replacement, http://bitlu.com/itemdetail.php?itemvar=100114320 is polycarbonate plastic drink lids, no hole. maybe something like that could be multi-lammed up with epoxy after scuffing the surfaces for adhesion.. glue and clamp 8 or more together tight? if the size is good, 1000 lids like that could make 100 sat dishes or more. it -looks- like about 1/3 of a sphere, or 2/3 hemisphere, but how big?

aha, ok.. about 120mm diameter roughly 4-3/4", might be just about the size of a jumbo drink dome lid.
not trying at all to waste your time and effort Swinks, its soooo not my style or idea of a good time!
really scuffed up surfaces and epoxy lammed could be an at home do it solution, if theyre available at size.
the poly being shatterproof and the epoxy semi flexible tough when cured, probably endure abuses well enough.
some of the poly CCTV cam-domes look promising too but 30 bucks each could get spendy if cut-drilled wrong.

http://www.amazon.com/Karat-Paper-Container-130mm-600pcs/dp/B003E6ZU9I/ref=sr_1_1 http://www.cupdepot.com/PET-Dome-Lid-for-20-oz-Paper-Cold-Hot-Food-Container-1000pcs-ctn-130mm-NEW same item I think, might be just about right size for lamming up after the snap-down is trimmed away, but that flat center dot.. idk. might be if one wasnt trimmed out it could act as a buffer for ball to magnet metal to metal impact? might be a BAD shape feature too, idk, if its enough of a bump to the ball that the magnet couldnt grab, ouch!

with a scuffed epoxy laminated stack, the last inside one could get its back polycarbonate painted before epoxied in so the inside face is clear-clean-shiny poly. paint embedded protected. 600 is a lot of lids, it might make 50 dishes, the back layers of plastic might need relief slits to lam them tight without wrinkling, theyed probably get pretty rigid within 3-4 layers. idk if this is a good idea-plan or a setup to be a messy FAIL, if they did lam up allright between the poly and epoxy it'd be like plywood tough shatterproof at least (learned much with a boatbuilding hobby).
also dont know if lids like these are available in a smaller quantity, someone might get lucky buying a dozen of em from some local ice cream shop for a couple bucks to give it a whirl?

also possible, just one of those lids polycarbonate painted outside, then laid up with fiberglass cloth and epoxy resin to be as thick-strong as needed, could avoid issues (and bubbles) of trying to lam several layers of lids exactly the same size that might wrinkle up trying to force them together. hobby shop or online, 2-4oz fiberglass cloth would take a whole lot of layers but it lays down pretty nicely. they also likely have faster curing epoxy resins.

the 3D printing is REALLY GREAT, absolutely! this dome lid epoxyglass idea just another possible option for replacing something broken. broken stuff always a bummer..

that onion keeper looks pretty darn close if you can trim and drill it. might be a little flexy-bouncy idk. I know the cup lid would be rock solid enough with 3/16 thick epoxyglass behind it, regular polyester fiberglass resin probably not so much with a pinball being launched into it fairly brutally. the tupperware just might hold up a good while if its got some support (washers both sides?) at its mount screws, I sure like the "make it work NOW" part.

idk, that ramp looks more a candidate for vaccuforming to me Tsskinne, but you might be able to repair existing with light 2oz cloth and epoxy resin too, idk how bad it is. one layer cloth to the inside, whatever fill needed where theres a problem, and a couple layers or more to the underside for strength-reenforcement. epoxy resin and the 2oz cloth will be very thin and near transparent on the inside. sanded really smooth then a thin layer of the resin with a cloth (like a clearcoat) and let it dry a couple days, should be stronger than new. got a real RC hobbyshop nearby?
its easy to work with other than fingers getting sticky, not obnoxious fumes like fiberglass polyester resin.

ebay.com link: Goldeneye Satellite dish

not bad, the price might go crazy, or not.

that panel look, very cool swinks! much better looking than the stock one to me.

I wouldnt doubt the mushrooming caused center outward stress Doozie, the cracking sure indicates it! the original plexi probably puts up with a lot until that starts happening. I really like that new panelled look swinks, and under 100 bucks seems a GREAT deal for whats not likely to get broken again. the gray nylon, left plain nylon and lightly hit with silver paint then lightly sanded to leave the silver down in the texturing (the ball aint gonna get that anyhow) might be better than aluminum flake into the plastic itself, I get it about the dissimilar materials thing and that metallic look sure nice!