There is one in Henne Mines, one in Pharos of Ridorana, a random treasure in Cerobi Steppe cares one (Diamond Armlet equipped). Vishno drops it as a rare item. Level 99 Red Chocobo in Ozmone Plains drops one after killing a certain number of Chocobos.

From an FAQ on GameFAQs. Search "13-2." to find out the requirements needed.