The JG VSR Bar 10 is a great cheap sniper. I've seen it around for about $120-140, and stock, it's pretty damn good. It's easily upgradeable, and there are many mods you can do on your own to improve it. Cheeseman can hook you up with a "pimped out" one that will dominate, but it'll cost more. There's an article about which L96 clones are good somewhere on here as well.