Strange hard-chine dinghy...help identify

This popped up on our local Craigslist. It's apparently fiberglass, but there's an interior floor of plywood. Note the inboard rudder! The rudder post is raked. Owner originally said that it's 13 feet but has revised that to "bigger than my 13 foot Boston Whaler so maybe 15 feet". It's a daggerboard boat....wild. I'll post pics of the board and the mainsail logo.

Does anybody have any idea what the heck this is?

 

I want a little 14-15 footer for some dinghy cruising and casual daysailing. I have a pic of the daggerboard case, there's actually a lot of room forward of the case, to the mast, so there's sleeping space. However, if this is a total mystery boat I'm tempted to do this with it....

 

Might be what's left of an old National One Design. The design dates to 1936. Some were built in fiberglass by Ray Greene an Co. in the '60s. No clue what the sail emblem goes to, though.

https://sailboatdata.com/sailboat/national-one-design/