I am currently working on an aluminum boat. It has absolutely no identifying marks - no paint, no placards, no numbers or stamps, nothing. Guy I bought it from said it might be an Aerocraft, and then his wife said something about it being made by Boeing.
The lack of any cast pieces on this boat lead me to wonder whether or not it's some sort of home made? It certainly wouldn't be too hard to believe that a handy guy who worked with aluminum for living couldn't build such a nice piece at home. Maybe somebody who worked on airplanes for a living?
Built by someone who worked at Boeing? Wouldn't surprise me at all. My Dad worked at Boeing for 40 years (give or take a few) He said they had a lot of scrap aluminum lying around and that workers would help themselves to it occasionally.
Also Boeing was experimenting with small hydrofoil boats in the 60's. The best known one was called Little squirt. I believe they were aluminum. I used to see it running around on Lake Washington. It made a lot of noise.