Well cleric epic is always carried, in terms of equiping it, you will be hard pressed to find upgrades. They either come from North Temple of Veeshan or your clickies/toys in Veeshan's Peak and Sleeper's Tomb.
In terms of an actual upgrade to wear all the time over epic, there is really just one choice for the discerning cleric,
Blackstar, Mace of Night.
If you need slightly better resists for slightly less hp/mana,
Sprinkler of the Spirits.
Once the Celestial Elixir BP and Donals BP nerfs are completed, clerics can only rely upon
Shissar Apothic Staff for free unlimited clickie heals.
For funsies, Clerics can pick up
Primal Velium Battlehammer or
Primal/Priceless Velium Brawl Sticks.