That's tough. I'd really like to fit in a 670, as they're by far the best value at the top of the GPU heap, but you can't fit in both a 670 and a data hard drive (in addition to the SSD) on $1300. Do you have any interest in getting by without an extra hard drive, on the SSD alone?
Here's a decent build minus the extra hard drive. If you don't already have a copy of Windows and need to fit it in on this budget too, you'll have to drop more things. http://www.ibuypower.com/Store/Intel_Z77_Core_i5_Configurator/w/127809