Never had a problem with the starter when swapping gearboxes, but I always used the original flywheel (A12, A14 or A15, no matter which tranny)... so nothing changed there.

When changing gearboxes, the starter has to be removed/unbolted anyways. It's a good time to repair it.

Take the starter off and make sure that the gear turns only one direction. If it "slips" (turns both directions), change the gear. This will cause it sometimes to spin the engine, other times to make a strange "whiz" sound.

If you decide to buy a new starter, get a Bosch.

do you happen to know the p/n of that bosch starter? (for an A series, right?)
Also, anytime is a good time to check/change your starter. It's probably the easiest thing to remove and replace. Oh wait, the distributor rotor is probably easier

I bought a Bosch starter around 1986 or so for my A12. I don't know if they still make 'em but worth asking it was so much better design. Bosch Starter dealers. There's one in Hayward.

[edit] looks like it's Part# F5000-11306, for a 1972 Datsun A12 manual transmission starter. Wow, only $30 at drivewire.com