Haven't read the whole thread so don't know if this has been suggested... Approach Moorings/Sunsail and get yourself taken on as crewed charter skipper with your partner as chef somewhere like the BVI. Not quite what you had in mind but more realistic than getting a free boat.

I lived and worked my Privilege in the BVI for a couple of years and it was a lot of fun for me as skipper. Wife didn't enjoy the chef role as much but she still had a great time when we weren't chartering.