Dak

If all you need is essentially a TII drive shaft that mounts to a N/A rear end like djSL mentioned. Mazdatrix has you covered. Just pick your poison. Steel or Aluminum
DRIVESHAFT, 86-92 NON TURBO WITH TURBO TRANSMISSION - Mazdatrix
DRIVESHAFT ALUMINUM, 86-92 NON TURBO WITH TURBO TRANSMISSION - Mazdatrix
If you need a custom length you can get Mazdatrix to make you one or for a little more money than Mazdatrix's steel shaft you can get an aluminum one from these guys.3'' Aluminum Driveshaft - Up to 500 HP - Precision Shaft Technologies (pstds.com) I got one in my car. I supplied the front yoke, rear flange and U-joints because to me it seemed easier to just supply them than explain what I needed since you have to use a conversion U-joint due to the yoke and the driveshaft from PST using a different joint. This thread explains it pretty well. How to make your own aluminum or carbon driveshaft - RX7Club.com - Mazda RX7 Forum
I think I got my yokes and U-joints from Northern Drivetrain. Northern Drivetrain, LLC