I like to play 4 players sit n go heads up (2 match in a row wins it all)

$1.50 buy-in , rake 6.7%, winner takes all ($5.60)

The match has been going on for a while I've dominated in the beginning, 1800 to 1200 and then he came back with a big hand I flopped top pair top kicker, I was down to 200 vs 2800 and got back to 1500 and now I have this hand.

blinds 3 mins, no ante

He has been robbing post flop play like crazy with low blinds early in the match and showing his hands that was pure bluff missed str8/flush, showing 34s and chit like that, I never build a big pot unless I have a good hand most of the time at these low stakes they spew chips here and there.

10/20 , 15/30, 20/40, 25/50, 30/60, 40/80, 50/100 etc

were up to 50/100 blinds , back to 1500 chips each

Now I have A7o on btn, I raise to 300 , he shoves , do you call or wait for a better scenario to outbeat him post flop ?

At 15bb's I would call A7o after a minraise if you decide to minraise even against population, and even more so against aggressive villains, plus you raised 3x which makes it an even more clear call. Winrate maxing is when you have a very thin +EV call you can fold. Not sure what exactly he shoves here when you raise too big pre-flop, but I don't think it's close at all.

If you raise should just go for 2bb's and call it off.

He's been building pots when I have a pair and then shoving on river multiple times too..

I finally called and he shows ATo rigged haha jk.. they get good hands once in a while.. he has reraised shoved me in the past too preflop so its not like it was the first time

Its best to taper your raise sizes downwards from 3x at the start of the tournament down to 2.1x or even 2x. When you are in the 15bb scenario its important to assess how often villain is shoving over your raise. If its a lot you may want to forgo the raise all together and whatever you'd raise-fold, just fold instead and open shove your raise call range. I don't do it myself but a balanced limp strategy may be also viable.

The idea of waiting for a better spot is something I'd avoid and partly why villains strategy might work. They'll shove junk because they see you're a good player who can raise fold. Think longer term about how often you'll be in this spot and make the best choice that will work best on average.