That is a pretty short time, and not sure that the charter
companies would do that, You might try Caribbean
Yacht Charters, in French Town. But even that may not be doable.
However, back when we were doing our two week charters with the moorings and sunsail out of road harbor, I did see that they had nice sailing vessels, maybe 18 ft, or so, for their training classes
. Perhaps a charter
co. on St. Thomas might have a similar program