A water staff is useful for repose
Light or Apollo's staff for Repose. Anything else is wrong. Please stop saying things like this, because if I see one more person using a water staff for divine magic, I'm going to lose it.
As for gear from NMs, couldn't tell you.
As for gear in general, I'd make sure you have a good resting set. Dark Staff alone is not okay. Get a Qiqirn Sash +1, a Seer's Tunic, some Baron's Slops, a Cobra Hat (At 55.), a Beak Necklace +1, and anything else with hMP on it, and macro it in when you rest. This, along with some ginger cookies, will make your MP come back a ton faster, and make you a better overall WHM.