How to tell if synchros are good?

["John F Sandhoff" <sandhoff@csus.edu>]

I'm finally putting this 4 speed back together.

Is there a good way to tell the condition of the synchros?
Or is it best to just play safe and replace them now? If
I replace them, do I also replace the synchronizer bands?
I haven't checked with the usual suspects yet - anyone
know for sure if the synchros are still available?
(parts like the countershaft have become hard to find...)

-- John
     John F Sandhoff   sandhoff@csus.edu   Sacramento, CA