Remember with rotaries the exhaust ports are on the drivers side of the car, this means you're going to have a fun time figuring out an exhaust to suit

There is that 20b sprinter in Japan, it was converted to LHD for this reason.

My friend had engine mounts for 13btt/Ke70. They came from an Orange Ke70 that used to run 13bpp or 13btt from memory, Big flares, dish and shopping trolley wing. It was bought by a mate and then parted out. I'll see if he still has it.

Engine mount, Gearbox X member, Tail shaft + yoke, Diff, exhaust and inlet piping, fuel setup, ECU, wiring, Tune, Injectors, Ext gate, Turbo.....

As said above, what you can do yourself is where you will save the cash. Rotaries are fucked, people will rip you off.

IMO buy a half cut 13bt and run close to standard. With a light car, you will be able to crack 10's for $10k if you do most of the work yourself.. Hope that helps.

Michael