This item only still drops on Al'kabor off of Overseer Gnerpokkel in Grimling Forest. It is used in the quest "General's Challenge" which is also in Grimling Forest.
Overseer Gnerpokkel is not listed on Allah's. Please create a listing if possible. I'll glady post a picture of him later. His drop table is the same as Corrupter Ahgra, except for Corrupter Ahgra's head, and instead drops his heart.