You machinists out there will probably cringe when you read this, but here's how I just made my retaining pins using a dremel tool and cordless drill.
Basically:
1. Use cutoff-wheel on dremel tool to cut two straight pieces from the long side of an allen wrench. The wrench was should obviously be bigger than the bigger-sized holes in the gears (sorry don't know what actual size I used was).
2. Put the first piece in drill chuck - it holds an allen wrench real nice!
3. Hold the trigger down on the drill or lock it in place, and file away what you want w/ the cutoff wheel on the dremel.
4. Repeat w/ other piece.
If I was going to do it again, I'd probably use a non-rusty allen wrench as stock since it would turn smoother. Oh, and it helps to make sure the dremel tool and drill are turning in opposite directions. Here are some pics.
End Result: 
Po' Man's Lathe: 
Anyway this only took me about 30 minutes, and sure beats waiting for the part when I have 6 shims to mic.
