Now you're talking
At last, El Reg comes to my part of the world. Perhaps I can help! To wit:
1. I've got a Cesaroni J engine (might be 3G) that's yours for the asking, and the usual adapters for fitting different dia. vehicles. Only hitch is that I'm up in Seattle. Can't get these at Walmart, but the courier delivery guy did drop it off at my house, only after I promised over the phone to lie to his boss and say I was physically present when he dropped off (this hazardous material). So yes it's relatively easy to ship these in US of A.
2. My folks live in New Mexico, unfortunately, way up in Santa Fe. But they have lots of friends and might find you a place to stay down in Las Cruces. How many of you will there be?
3. Why bother with the Caribbean after the flight? You've got one of the most interesting places in the USA to explore. For starters, White Sands missile range is close by, as is Alamogordo. Both have missile or space museums... Then there's El Paso TX, go to the ('murican) Taco Bell there, it's surreal... If you time your visit right you might even get to visit the Trinity Site.