Not a problem for you (maybe). The US law prohibits using US ports
for trading with the enemy (Cuba) and foreign-flagged boats have run afoul of this in the past. Boats do go directly from the US to Cuba, but I doubt many advertise this fact. It is best to return via the Bahamas
to avoid awkward questions. As far as finding a berth, you are doing the right thing: offer yourself on the internet
and hope someone will find you.