This item is no longer available in game.
Staff of Prehistoria was created by combining The Shaft of Tsol and Gni'kiv Medallion. "Tsol" and "Gni'kiv" are backward spellings of "lost" and "viking." It is a reference to The Lost Vikings, game developed by Blizzard Entertainment (named Silicon & Synapse at the time) in 1992.
Interesting fact: Due to the item quality and Bind-on-Pickup status of both the staff and the medallion, Uldaman dungeon groups had to be careful that only one player looted both; otherwise, the party would be unable to unlock the door to Ironaya's room. Blizzard finally made both items Rare quality so they could be traded between party members, and then removed their BoP flag entirely.
Side-note: I saw the Staff of Prehistoria for sale on the Auction House early in Cataclysm but didn't want to buy it at its listed price. I still am kicking myself to this day for that decision.
Prior to Patch 4.1.0, this had been required in order to access Ironaya, an Uldaman boss. Using it in the Map Room played a unique sound effect. While I have been unable to find a mention of the sound file, I can say that it sounded very similar to this.