Tome of Diabolic Remedy Trinket (patch 2.4.3)

Tome of Diabolic Remedy - If you are not an alchemist, or if you don't have access to Illidan, then this is the best healing trinket for you. It has a passive 18 mp5, and when big heals are needed, you can always use the trinket's ability to give yourself an extra 396 healing bonus for 20 seconds (2 minute cooldown).

This trinket drops off Hexlord from Zul'Aman, and you can do ZA twice a week.