$80?! I want THAT deal. I generally see original "vintage" He-Man complete with weapons and armor for like $130+. For $80 he'd be missing parts, probably.
But yeah the demand for all things MOTU has skyrocketed in recent years. All the 80s kids having YouTube channels is probably a lot to do with it. Same reason why every time AVGN and Sega Lord X talk about a game or system, it shoots up in price online because now everybody wants it.