You can order the PCP&C Silencer 610 directly from PCP&C:http://www.pcpowercooling.com/products/viewproduct.php?show=S61EPS&view=about
= $119 + whatever shipping is.
The Corsair 550VX is cheaper at ZipZoomFly CORSAIR CMPSU-550VX 550W
= $63.90 after $20 rebate. Also no shipping charges. Newegg.com charges another $8 - $9 for shipping.
The Silencer 610 is the better PSU, but he Corsair VX can definitely hold it's own. So I guess I would choose the Cosair VX (from ZipZoomfly).