You can rule out the GX2 550 off the bat, it's not as good as the XFX unit even though it costs more. XFX TS 550 is a Seasonic built unit, should be very good. With 5year warranty, I'd expect it to have all solid caps as well. There's a Bronze and a Gold version of this unit, but 50 bucks is a great price either way.
Cooler Master V550 is built by Enhance. Seasonic is generally better than Enhance, although Techpowerup did review the V550S and gave it an 8.9, it should be a nice unit. Still, the only reason to pay extra for the V550 over the XFX TS550 Bronze is higher efficiency, which isn't worth much at all, maybe 5-10 bucks.
That EVGA 500W unit is way below the quality of the other units mentioned, I don't recommend it. It has only 3 year warranty, only 80plus efficiency, and it's built by HEC which isn't exactly known for producing high quality stuff, although their collaboration with EVGA seems to be a bit higher quality than you'd normally expect from them. In any case, Seasonic and Enhance >> HEC.
In terms of power requirements, 500-550W is the correct size to get, although some 400-450W units also do come with the necessary PCIe connectors. Your rig will be using only around 200-250 watts while gaming, so a
Rosewill Capstone 450W would also work fine. $55 for a Gold unit with top quality and 7 year warranty. The 550W unit is $10 more if you want to future proof your PC a bit for more power hungry components.