Excellent suggestion! You might also try the other sailing sponsors listed on the BVI sponsors tab, as they may well do a nude charter, even though it's not specificially advertised on their home pages. Check with Catatonic and Sail Bella Vita. Not sure if they would do it or not.

To the OP, from what I understand, you probably should decide WHICH islands you want to sail in, BVI or St. Martin, as the passage between them apparently is extremely rough, even though they are not that far apart. I am a total landlubber, but as I understand it, you could do SXM/Anguilla/St. Barts OR you could do the BVI and USVI, but definitely not both.