Kappowe, airsplat, airsoftgi, and trintyairsoft are all good sites. I suggest a Dboys or Tokyo Marui I have had good experience with both but the Tokyo is gonna cost you more.
Also focus on the metal gear box, high accuracy 275-350 FPS guns if you are doing CQB which usually only allows semi-auto.
For woods or any other focus on 300+ FPS and high mag capacity.