The 2-3 synchronizer assembly is sold as a unit, but it might be possible to just replace the brass blocker rings if the steel shift collar isn't badly worn. Try Todd's Auto Parts on 1st. Avenue North in Nashville. They sort of specialize in old stuff, so if they don't have what you need they can probably steer you in the right direction. While you're there, ask about a "small parts kit" that includes thrust washers, needle bearings, and other stuff necessary to freshen up a tired transmission.

I have the non-OD version of that transmission, and I'd be willing to part with it for a reasonable amount, or maybe some kind of horsetrade. I believe everything ahead of the OD unit is identical, including the synchro. Drop me a PM.
Jerry

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