The dance music guide lists the theme from the James Bond movie Goldfinger as a rumba. That would lend itself to some interesting costume choices. You can get gold body paint from a theatrical makeup supply like Ben Nye.
(Fallen from Pretty Woman) It's a good American Rumba.
There are also several Rumbas from Strictly Ballroom -- Perhaps, Perhaps, Perhaps; Time After Time. Just heard "The Streets of Philadelphia" by Bruuuuce Springsteen on the radio a little while ago. More international-speed Rumba, if that's what you're looking for.