I have camped the Grol Baku camp near the small lake in SD for a long long time. I have prolly killed the keeper somewhere between 40-60 times and I have never seen this drop. He can also drop Follower's Sleeves, Bracer of Defense and a low end caster 2hb along with a low end caster robe.
Dollo Might 54 Druid
Mystic Dawn
Luclin