We have our Mazdaspeed MX5/Miata intercooler upgrade kit available now. The retail price on the kit is $799. I have attached a few pictures of the kit.
The kit replaces all of the piping with a 2.25 mandrel bent aluminum set. The kits is supplied with a larger intercooler, new turbo inlet pipe, and all the needed hardware. On a completely stock car you will see a gain if 12-14 hp at the wheels.