I'm guessing you know a mate of mine called John French.
Whoops just realised I hadn't answered his text about wheel bearings for you.
These would be Mazda only parts and it will be cheaper to buy complete used shafts. Worth knowing I’ve never know one to die yet, and I put 500bhp through the ones on the race car.
Keep us posted on your progress
Just thought , I'm sure RX-7FD ones are the same so Craig who does the V8 conversions may be able to help with the drive shafts