It is actually quite rare, not a common drop from the Pale Count. I wouldn't say it is worth a lot of money since The Pale Count respawns relatively frequently, it is not that hard to kill the boss, and the item is just decorative (as far as we know).
Depending on the server, you can assign a price. On Antica, the average selling price is 80k, while on Solidera, there are 3 medals for sale at 300k each.