This item comes from a special loot card from the Fires of Outland set of the World of Warcraft Trading Card Game. When you redeem the code from <The Black Flame>, the item will appear directly into your inventory, no purchase necessary.
The odds of pulling a Spectral Tiger Loot card out of a Fires of Outland TCG pack are speculated to be around 1 in 7,260. The first Spectral Tiger card sold on eBay for $2,000. Cards currently sell in the range of $500 to $800 on eBay.
This mount is also BoE so it can be sold on the auction house for a large amount of gold. (anywhere from 40k to 500k)
Unlike other loot cards in WOW TCG sets 1 and 2, this loot item requires you to spend gold to acquire it. This is because the loot items are not supposed to affect gameplay by giving a player an advantage over another, thus, it merely unlocks the option to purchase a different mount rather than giving away a free mount.