I am havng a problem with the left drive axle comming off when I turn. I could not find a link to the size of o-rings to use to take up some slack. Any help would be appreciated.

you can cut a piece of fuel line and put it in the drive cup that will take up some slack

i have had a bunch of problems with that, mine was because the bottom spindle screw had come loose or out completely and would let it flex just enough to pop the axle out on a hard hit or real sharp turn. check that out too. if they are loose, put a little superglue on the threads so it doesnt happen again.