The Travelers
I've pasted a copy of my "Monks of the Horizon" from my own world. They're not a PrC but they are healing monks. Take what you like.
Monks: There are 3 orders of monks on Ert. All monks are human. Two are open to PC's, normally. All 3 orders are composed of acolytes to certain clerical orders. As a result, all monks on Ert have the ability to cast clerical cantrips, as would a 1st level cleric.
All monks are capable of fighting into their CO (they don't go unconscious at 0 hp). All monks gain the "Ambidexterity" feat for free.
A. Monks of the Horizon, "The Travelers" (Fharlangh)
A Traveler can be identified by his brown cowled habit and the wooden holy symbol of his god hanging from his cord belt. More often than not, he will be carrying a quarterstaff. He is always LN. Heal is a class skill. At 1st level a Monk of the Horizon gains the "Granted Power" of the Travel Domain for clerics.
At 6th level, instead of the "Improved Trip" feat, Travelers gain prayer as a cleric of the same level 3x/day. At 15th level, instead of "Quivering Palm", Travelers gain mass heal as a cleric of the same level once per day.