I'll go with the 80's as well. Cool find. I had a Greg Noll V-bottom that was dug out of the trash. It had a lot of dings, but the removable, huge, Lexan fin was still intact and the box was good. I patched all the dings. lol. It was a lot of work. By the time I had patched all the dings, (I put foam in most of the big ones instead of filler) and looked at all the sanding, I said F-it and just sanded the entire board, glossed it and then rubbed it out. Kind of. It would have been way easier to map the board, cut a new one finish it out and glass it. Anyway, I rode the board once. It was HORRIBLE. lol. The worst surfboard I have ever ridden. It was barely a surfboard. If you had made me ride that thing I would have quit surfing and taken up swimming or poking myself in the eye with a sharp stick. 1968 sucked.
Then my father found an original Lance Carson model in the trash. The classic triple stringer pin tail. The infamous LC model that was a major thing at Malibu in the 60's. Still has a cult following. I started on that and the stringers had all rotted out. So I gave it to a shaper/glasser who has since hung himself and he gave up on it as well. The story goes on, but IMO that board was cursed. Long story.
The HF should be fun. Worthy find. Good luck with it.