How much is a unopened bottle of Jim Beam Whiskey 100th KY Derby worth?

Let me explain:

Unopened bottles of Jim Beam 100th Derby Commemorative Decanter typically sell for over $450 on Ebay and other sites. Some sellers are even asking $599. There was one listing for about $350, but it is already sold out. Some sites have the decanter listed for sale, but do not have any in stock right now.