I have a couple questions about the FC. First how much does the transmission cost for this thing? Second could you put the turbos for these things in other cars?

One more question abou the turbo. If the turbo is shot is it easy to fix?

 

You can find a lot of people selling used transmissions for around 100. im not sure on rebuild costs.

The stock turbos on these things are not good for most cyl engines. They have bigger exhaust housing compared to the size of the intake side.

The turbos are getting old, there are rebuild kits for them.

 

the Mazda turbo flanges are specific to the manifold that it sits on.
If you want to put on another Turbo (like a higher Hp t4 based turbo) then you have to get ALL the supporting modifications needed to allow that turbo to run correctly on the engine.
it is not just a Slap on and go kind of deal.
You need the fuel system and ECU supports to allow that proper running of the turbo on the engine.