Quoted from LTG:

Screws - http://pinrestore.com/Hardware.html 2/3rds of the way down.
LTG : )

Quoted from Manny65:

For the long return lane screws:
1. From http://creamyeagle.blogspot.com/2014/05/terminator-2-pinball-tear-down.html?m=1 (as per eyeamred2u post) they are a #4-40 x 2.5"
2. However the Part List from the T2 IPDB https://www.ipdb.org/machine.cgi?id=2524 doesn't show any 4-40 x 2.5" machine screws but rather 6 x 4006-01027-40 "ms 6-32X2 1/2 p-rwh". Note that there are various errors in the manuals, parts lists and websites so it does pay to check.
3. Using the 4006-01027-40 part number you can search the likes of Marco or Pinball Life. In this case Marco has them https://www.marcospecialties.com/pinball-parts/4006-01027-40 Or for this common hardware you can pick up replacement parts at hardware stores or other websites such as http://pinrestore.com/Hardware.html (as per LTG post) which is a great place for tools and other bits & pieces.
As for the smaller wood screws for the metal sleeves (there are 3 of them on that return lane and from your picture you have the 3rd)
1. From http://creamyeagle.blogspot.com/2014/05/terminator-2-pinball-tear-down.html?m=1 it says they're a #4 x 1" sheet metal screw
2. However the Part List shows 3 x 4204-01016-16 "ws #4 X 1 p-rh-a" - these are wood screws and given they are going into the PF it makes more sense
3. And here is the part at Marco's https://www.marcospecialties.com/pinball-parts/4204-01016-16
The metal sleeves are a bit tricker
1. From http://creamyeagle.blogspot.com/2014/05/terminator-2-pinball-tear-down.html?m=1 it says they're 1/2" high
2. I know the machine has 3 of these, so searched the Part List for "1/2" looking for a Qty of 3 and found these 3 x 02-4020 post-spacer 1/2"
3. And here is the part at Pinball Life https://www.pinballlife.com/williams-metal-lane-guide-spacer.html
QED