A suggestion, if I may. Your husband can get a suit on blair.com on payments if you have decent credit. For the Bahamas I would look to linen or silk. Another option is eBay, which has a suprising number of men's suits and tuxedos from around $50 up. JC Penny has tuxedos for about $99(plus cost of the extras which you can buy for under $60, but remember buying a tux is in the long run cheaper than renting. if you wanted a tux but didn't feel like a rental was justified. For tuxedoes in the Caribbean and the Bahamas, tropical wool is your most common option, though occassionally you will find silk ones. You must pay attention to fabric. Do not wear poly/wool or poly/silk blends. They hold in too much body heat. I also recommend a no vent jacket for a slimmer man and side vents for a man with a bit more girth. If you want any advice on where to find something for an inexpensive price, feel free to contact me. I am on a tight budget myself so I am always on the lookout for great deals. Below I am posting the RCCL dress code guideline for formal nights, from their website.
Q: What are the dress codes onboard?
A: There are three distinct types of evenings onboard: casual, smart casual and formal.
Suggested guidelines for these nights are:
Casual: Sport shirts and slacks for men, sundresses or pants for women
Smart Casual: Jackets and ties for men, dresses or pantsuits for women
Formal: Suits and ties or tuxedos for men, cocktail dresses for women.