Im using a hammers 3-9×32ao mil dot. Got it on amazon for around $50. Overall its a good scope. Does its job. It lacks a lot of features of higher priced scopes and the windage and elevation adjustments arent the easiest to work with. But again, cheap and accurate.
I agree with spash, try them both in your np. I know you have a phantom as well, Im not sure if i would shoot the 10.5gr out of the phantom. I have been told heavier pellets can cause excessive spring wear. Shouldnt be an issue in your np though.