there are a handfull of coldwater (Japanese) lionfish which never get into this country. They are cool looking and rare and its hard to say how they'll do, but if you got the dough
As for rhinopias, check out that link above, its links to a purple morph rhinopia eschmermeyersi, no ways its an $1800 fish. R eschermeyersi are the least rare rhinpoias and that one would retail for around $800. Eitherway its freakin gorgeous.
Anyway there are mor Xotic scorpionfish which you can do a google search for look for ambon lionfish, blue finned lionfish, rhinopia aphanes, Rhinopia frondosa, imicus, chorydactus.
Tghe tough part for you is to find these fish, as most wholesaler know what they got as far as rare and Xotoic so they send them off to high end clients (like Asia)first. If you know a cherry picker that the wholesaler you might be able to score something cool, it just costs $$$