As you say, a couple of petrol sterndrives (CR prob have a pair), few sheets of marine ply, a staple gun and 2 or 3 tubes of pink grip and the buyer will be quids in.... probably make 600k profit.
A bit more viable than that rather "lightweight" Sealine prototype hull that was punted around and the fire damaged Sealine 51 which loitered on the listings for ages ?