You could always get creative. These people got this boat home a long distance with this setup(the boat is beautiful now BTW).
Nice photo out of respect.
A boat doesn't become a dock potato if it's being used. With working engines would it be taken out often enough to make it worth it?
After googling the boat it looks like a decent candidate for diesels. I'd buy a pair of used ones for around $10,000(probably a pair of volvo's because they are plentiful), paint/freshen them up and swap them in.