Pre I'd probably just call because if someone calls your large squeeze, having 1010 in a 3-bet pot with a super low SPR isn't that great. We also get greater implied odds
if we hit our set, and we're almost closing the action. You're pretty much turning 1010 into a bluff here. I don't think a lot of worse hands are calling your 3-bet, and a better hand is never folding. You might even get shoved on by a worse hand like AK, and I don't think you're 3-bet/calling off here. Squeezing 1010 is pretty much the same thing as squeezing 22-99 here.
He's not really repping anything, but at the same time I don't think he's bluffing
300bb deep. I'd probably fold to the flop c-bet, especially with no reads.