Honestly, I'd spend it all on something else. Combat arms feels like it's going to be the next Dungeon Fighter online. I mean, it had a way better community, way less hackers, and it still got shut down due to "no support." And the way people keep saying it's gone to hell, I don't think they'll be making much money, and will eventually shut down. Your NX will basically just be wasted. Unless you just want something short term anyways.
I'd get a subsonic, or arctic sniper. As well as probably a Kriss or a Raus