Hi "The Brewers",
You should get all the tux rental information in your docs and can pre-order the rental tux, usually around $100 dollars for the whole set and it usually includes 2 shirts. Recently my husband bought his own tux at a warehouse sale, got a great deal, they sold both used and new tux's, so you may want to keep an eye out for one of those type sales. Unfortunately, then your husband will have to pack/lug it with him, but they actually pay for themselves with just a few rentals, so if you think you have use for a tux and or more cruises in the future, its definitely something to think about.
Enjoy your Pride cruise