JR and Specktrum are compatible, but otherwise 2.4 stuff has to run the same brand rx/tx.

Hobby King offers cheap orange rx receivers for Specktrum and I believe they also have a line for Futaba.

A used dx6 or 7 would be good bang for the buck. There are a lot of bind and fly planes that work with Specktrum.

As far as plug and play, modern radios are pretty much standard, so any reciever could be installed.