short answer, yes. long answer, yeeeeeeeeeeeeeeeeees.
1. the motor mounts need to be modified.
http://www.banzai-racing.com/ sells the mounts that you will need. they also have a very helpful support staff that is incredibly knowledgeable. i like them a lot.
2. you don't even want to try to use stock engine management on this motor. go ahead and do yourself a favor when the stock motor is coming out; tear up the harness and build a custom harness along with some after market management.
http://www.aaroncake.net/rx-7/megasquirt/ is a good place to look for specific advice. i like the megasquirt because of the freedom of self-tuning.
http://www.glensgarage.com/catalog/a...uirt-c-25.html is a place where you can find megasquirt ecu components. if you don't want to do that, you can check into other ecu options. i can say that the megasquirt is the cheapest option and it just takes a little more research and a lot more hands-on stuff.
3. going along with management, you will want to do a single swap. the stock twins are really hard to tune with, so just do yourself a favor and swap for a single set-up. it will net you more power in the end anyways.
4. if you do find an re motor stateside, i recommend a rebuild. it is seldom that people sell a perfectly good re motor.