It might be fun just to take along a mask ... maybe a Mardi Gras type mask that would look great with your formal outfit? Or one of those whole-head masks representing a famous person? That could play He!! with your hairdo, though.
Sorry that this was not more timely, but I just came back from a Halloween cruise aboard MV Sun Princess. We did have a Halloween party aboard the ship, complete with a competition for best costume in which my home-brewed sci-fi chaplain took third place. Creativity seemed to score very high marks in the judging!