Well I couldn’t find anything. So I tried 2 different approaches.
I drilled out a 8mm bore pulley going only .4mm a pass so 8.4, 8.8, 9.2. 9.6, 10, 10.2
this worked much better than trying to start sight off with a 10mm bit, not perfect but usable. I drilled out.2mm more to get it to fit easier on the 10mm motor shaft. and I had to file the keyway back in.
Removed one flange and ground down the the 15mm wide 10mm bore Alien pulley to 12mm
since I don’t need the flange for my project (the wheel pulley has them)
This worked out great.
Sorry to thread jack but I’m looking for a pulley for my motor I would like to purchase from @torqueboards but not a fan of the $10 shipping but on such a tiny piece