Of late I been buying a lot of factory OC'd cards. Used to be that the prevailing logic was OC it yaself, why pay them ..... but that mindset is no longer valid as:
1. Vendors now "binning" their products
2. OC'd models oft have oversized coolers and other improvements.
3. They are oft same cost as reference cards.
Now I gotta tell ya tho that I had an 18 month battle w/ EVGA over a factory OC'd GTX 295 that I had to RMA 5 times. I swapped it out with borrowed twin Asus 560 Ti's which were also OC'd by a much larger margin and they had no problem in same box, thereby pinning the problem down to the EVGA card. Finally EVGA sent me a reference 480 which has been performing well enough.
I have OC'd 7 of these to 1000MHz .... w/ no voltage boost . The 8th took a single notch voltage boost to make stable at 1000MHz....It's $30 over ya budget tho. However, it comes with new Batman game so there's ya $30 back http://www.newegg.com/Product/Product.aspx?Item=N82E16814121425
Is the card you looking at a 560 or a 560 Ti .... if the former, I'd skip it.