For travel insurance, our agency uses Access America and the website is http://www.accessamerica.com
The rates varies by the type of coverage, age, amount, etc. But you can get a quote from the website.
In addition, I uses them myself and they are very good. I beleive the cut off date is when the final payment is due. But you can call the company for more info.
As far as the destinations all of them are great and I can't imagine telling you any don't. But do try the new water park in Labadee.
Enjoy and have a great time.