Sanyo M9860 idler tire(s)

Anyone know what size idler tire is on the playback side of the mech? Mine is all cracked. Also, is there supposed to be a tire of some sort on the flywheel for the FF/REW? Currently it's metal-on-plastic and the FF/REW are slipping. The mechanism looks very similar to that used in the 9935K. I don't have that one with me here so I can't check if they're the same. FM is also weak and has a hum/buzz. AM is fine.

Well, using my handy measure-a-belt tool, it looks as though the tire was roughly 9/16" inner diameter with a thickness of .062". Outer diameter is either ~2cm or .75" if I remember the gauge correctly.

Since I have to wait for postage, I decided I'd get a quick fix from Ace Hardware. They have a nice selection of O-rings for roughly $0.49 each. Found one that fit nicely. Plays great. Also, I added three to the flywheel. There must have been something rubber on there before, as she rewinds and fast forwards like a champ now. These tricks should also apply to the 9935K, as I mentioned before. If anyone is curious, square belt sizes are 10.0" for the flywheel and 5.4" for the auto-stop.