There's a company called Floating Formals which offers a full tux outfit, with 2 shirts and shoes, for $85 (or $75 sans shoes). They were recommended to me by NCL, but I'm not sure whether they service other Miami lines or other ports. The tux is in your stateroom when you board, and you just leave it there when you return to port. Check them out at (888) 833-5621. Good luck.