What about a PG Xenon 600.1 it does rated power from 1-4 ohms, and they are rated higher than that, there is one one here in the birthsheet section that was rated at I think 834 RMS @4ohms
I would be careful buying a jl audio v1 series amp. Because it will probally be a remanufactured one. Go ahead and get a v2 series amp there a tad better anyway.
The one pictured in Ebay is not a PG 600.1, so you will have to confirm with the seller that he is selling the 600.1, the one pictured looks like a 4 channel