It is $760 for this XR0904 ring with 2ct GHI color crushed ice elongated oval moissanite center,moissanite accents in 14k white gold.

And the  XR0860 wedding band is $484 for this band with moissanite in 14k white gold.

So the ring set is $1244.

With 20% off,the price difference is $479.2（$1244×0.8-$645×0.8）.