Nat Pagle only offers this item for sale to mages. If your character is some other class, you will not see it listed in his inventory. If your character is Exalted with The Anglers then you will pay only 750 gold.
The item's name is a reference to Bipsi Frostflinger, a mage trainer in Dun Morogh who teaches Alliance mages how to cast Frost Nova. There is one other reference to Bipsi in the game - Bipsi's Gloves.
There is no way, ever, that I'll have a second character exalted with Nat Pagle. Because %$#* that guy. ┻━┻ ︵ヽ(`Д´)ﾉ︵ ┻━┻
┬──┬ ノ( ゜-゜ノ) Don't flip innocent tables, Alayea. Flip Nat Pagle instead, like so. （╯°□°）╯︵(\ .o.)\