Any frame from 04-06 will work. Make sure you get all the bits (tailgate bar, retainer clips, door surrounds).
Bestop will start selling a factory style replacement hardware set soon. It's basically the same hardware from a Supertop NX, and the only reason we aren't selling it right now is that we're using all the hardware for the back-ordered tops. I'm guessing as soon as next month though.
EDIT: I just read IndyJeepMans post: you can get the parts he doesn't have. They're not super cheap if you buy them new from Mopar, but they are available. Or again, you can wait for ours to get to market.