There's rockauto.com if you didn't know that one already, there mostly replacement parts though. What kind of aftermarket parts are you wanting? And i don't think mazda b22 and performance can really be used in the same sentence haha.
Well b22 nd performance can be used in the same sentance I'm pushin 140 hp nd 320 tq I upgrade my block bored it out to the max got bigger pistons nd smaller rings and compression is at 320 at each piston and went with forged crank nd rods nd have a 2 quart oil cooler other than that it's still stock but I wanna go with a different head make everything upstairs forged nd bore it out to the max