Hi Connor, Welcome to the club. That's a great rig you'll have there. Are you running your bass stereo?
+1 on what Loch (lmiwa) said. You can often find absolute steals on state-of-the-art amps from the '80's and '90's. Nobody wants to lug the weight anymore, but they sound way better with their big 'ol iron transformers compared to digital amps.
Crests are my favorite, but Crown and QSC are great, too. What you're looking for are Crest amps named either fa-901, 1201 or 2401, la 601,901, or 1201, Pro 3301, 4801, 6001, 7001, 8001, or maybe a ca2, ca4, or ca6.
Good luck. I don't know as much about Crown or QSC model numbers.
Oh, yes, a lot of these will eat your speakers if you clip them, so watch out for the argry red light.
Heck, I just did a search and found a cpx900 b-stock for 220 BIN and 30 bucks shipping. That would hook you right up. It's not really old but it is class AB, and weighs enough!