smvnmy computer runs tf2 at about 500 fps using comanglias cfg and parts were 600$ when I built it 2 years back.
i5 3550 3.2 ghz was like ~200$
gtx 650 ti 2gb vram ~100$
asrock z77 pro 4 mobo ~ 150
8gb ram, don't rember price but it was under 100
2tb hard drive 80$.
some of this stuff will probably be cheaper since its 2 years after, but this build has been very reliable for me. getting a 144hz monitor, a nice keyboard, and a nice mouse is definitely worth it but it can be pricy will extend your budget
8GB RAM is around $60 nowadays
also you forgot your PSU and case
PhunkLogical increments isn't a very good start for things like tf2 where the needs are pretty unique
Also just wait for setsul before you do anything based on what anyone else says
setsul isn't the only one that can do this you know ;_;