Each faction has one ring that in a lot of cases is BiS, I don't know about the second ring... but if it's like back in the days, with a lower number of twinks, with the inflated WotLK-market, it should be about 250g.
It's a ring that people looking for max ap will want. It's worth 50-100g. And this is certainly better than Meadow Ring of Eluding now (though it seems to be less rare and less desired bc everyone sees Eluding and remembers the days when it was bis - though those days are gone).