I too am no PSU guru. But I looked up this one
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341018
Beyond Reputable Company in OCz.
700 watts which will work great with your setup. Crossfire Ready.
Cost 99 dollars.
But if you buy it before the 28th you can get it for 89.00 dollars.
Sorry if this doesnt help. I tried...
EDIT: i was in the process of writing this post before dude_56013 posted his choices.