PMP makes pontoons out of Florida, and started in 2007. I don't think yours was made by the pontoons company.
There was a way to find out who had the manufacturers hin initials prior to the current owners. If that makes sense. I just couldn't find it.
The round transom hole for the jet bowl reminds me of a superjet. Who made the superjet, Hondo? Sanger? I can't remember.
Regardless, looks like a cool project. What are your plans? Big horsepower? Mild cruiser? Yard art?
Dan'l