So… my shop has a couple of these, but I need to order some more for my team. Does anyone know the part number and location of these 18 tooth sprockets? *Apart from RobotMesh’s website, they don’t ship to my state 
*
PS - I am building a mini-chain bot lift for ITZ, if there is quick and easy way to get around this PLEASE let me know <3
I assume you want the circular inserts for your chain bar. One very easy way to get around this is to either a) drill/file holes in the sprocket
or
b) use the circular inserts in a high strength gear with your metal directly screwed into the gear. 323Z made an excellent explanation of this way in this video. Explanation Of Om-Nom V2.0 - YouTube
If this isn’t what you wanted to know exactly let me know. Except I have no clue how to get the sprockets.
How to get them:
The last set I ordered had the HS shaft holes in them and came with full sets of both inserts. YMMV
If you want to put a screw in the normal size hole sprockets, I have drilled them out with a 3/16" drill bit(I think, the numbers are really scratched).
If you want to put a HS shaft through the sprocket there is not much you can do, other than order some.
5/32 drill bit is the right size for a 8-32 screw, FYI. So you could always just drill out the center.
I believe you are mistaken… the screws measure about 0.164", and 5/32 is only 0.156. That is not going to fit, let alone spin with very little friction.
3/16" comes out to 0.1875, which is a 20 thou clearance on the threads.
Actually, I was slightly off. Just checked the drill bit I use, and it is an 11/64, or 0.172". This is a little under 10 thou of clearance in theory, but the hole will probably end up bigger.
Hopefully I didn’t cause anyone to drill too many 3/16" holes in the last 11 hours.