Yeah, I've only seen a few of his signatures from the early 90's (because most pictures on Google are from SS), and I think they match. This one looks like he was already tired at the moment of signing tho.
So, would to say there's a high chance of this being real? I really want it, and honestly, right now this would be my best chance to get a signed ASM 300, but the answer from Beckett's quick review made me doubt. I'd like to see if there are more signatures like this (aside from those on the upper left on the Spider-Man #1 copies, which are very rushed).