you have a different parts definition that the dealer has.

To the manufacturer......what you are calling a snchro is actually called the "stop ring". They are about 40.00 each (3-5th)

The synchro is the stationary gear and slider that is used on the shafts to interlock into the opposing gears. those are about 275.00 for 3/4 and 242.00 5th-rev is i recall. Its been a couple years since i last priced one out.

the dealer will not sell you any parts for 1/2 unless you buy the entire output shaft and that was 1260.00 in 2004.

I suspect you either have or had a problem with a bent clutch fork. that would cause stress on the bearing collar. Or you have a clutch pressure plate issue that is bendign the clutch for and causing the bearing to not make even contact against the clutch spring fingers.