well that website has three-tier pricing for "standard" Isfahans in the size below (around the 1.7x1.1 m): USD ~2000, USD ~3000, USD ~ 4000
mostly driven by design considerations. The carpets below are in the upper end of the range for that size.
So in your mind, KAD, what is the definition of "real Serfian"? a rug attributed to the Original Serfian weavers "Mohammad Seirafian" / "Sadegh Seirafian" or any by any member of the Serfian family that is not copy?