As it stands, it's over budget. I think we can get it lower (without compromising build quality, of course). The PSU's suggested are pretty pricey. Perhaps we can start there?
Oh, I see. The EVGA Supernova
used to be affordable.
The XFX 1050w PSU (rebadged Seasonic) is only $10 more (AR) than the 850w Seasonic. I'd spend the extra $10. I have had great luck with XFX rebadged Seasonic PSU's.
Regarding the XFX being a rebadged Seasonic... not so fast. It is indeed a PSU based on Seasonic platform, that is for sure. What you should confirm is that is indeed made by Seasonic, not a Seasonic design with shitty components and made elsewhere.
While I could not find a review of the XFX 1050w at jonnyGuru every XFX PSU there have reviewed has been excellent. I personally have been mining with XFX PSU's for years without a hiccup. Can not say the same for crap OCZ PSU's I made the mistake of buying in the past.