Hueco Rock Ranch
I know about this campground because I'm an American Alpine Club member, but non-members can also access the lodging and campsites. It's a 3 mile drive to the park, but a nice option, given that the park only has about 20 campsites. Tent sites are $5 for AAC members, $10 for non-members. Facilities are communal including bathroom, shower, and fire pit