Recently I purchased a BRP MP62 that was originally fitted to a 99-00 Miata. I don't know if you can use any of this for any other year so please research that first. Since I am running an MS3 already I don't really have a need for the electrons that came with the kit. Probably not a big demand for this stuff but if you want to retain the OE ECU then maybe this can help you.
Main BRP ECU. Looks like it's plug and play into the OE ecu ports.
5th Injector Controller. The injector itself is located in the dummy throttle body but it looks to be JB welded in. If I can get it out without damaging it I'll include the injector too.
J&S Safeguard Ultra Knock Sensor
I also have some documentation/manuals from the PO so I can include what I have on a USB drive (or e-mail). $400 shipped to the low 48 for everything.