[Roadsters] 5-speed tranny pops out of 2nd gear?

[dickschnei at aol.com]

The transmission in my 1969 2000 is starting to pop out of 2nd gear.  It only
happens infrequently but once it occurs I can not use 2nd at all.  There is no
grinding or any other noise.  It simply goes right back into neutral.  If I
shut off the engine for a few minutes then restart, the transmission seems to
work normally once again.

This car has the Mikuni carbs and runs great, but I am fearful that if I drive
it under these conditions I might destroy the transmission.  Any advice from
anybody would be much appreciated.  I am not a mechanic at all, so any
solution would need to be done at a shop.  Are there rebuild 5-speeds
available?  Can these trannys be rebuilt at a local shop?  Are there even
parts available?   Any ideas, even ones that are of significant cost, will  be
helpful.

My wife and I love this car and enjoy the warm days taking road trips.  As we
approach our retirement years, we planned on taking this car on longer trips,
but in this condition it seems to be very risky.

Thanks,

Dick Schneiders