Do they have water fill stations available at camp ground?

No, they do not

They have water pumps. You just pump it by hand.

They have pump buts. I just called to ask for you .... Here's the number, call and YES they have fill stations--but they are PUMPS. 231-547-6641-Fishermans islands state park, charlavoix, mi

Not for RV's.

This state park is a rustic state park.

Not that I recall