Yes...there are many RV beach camping sites in North Carolina. Check out Carolina Beach State Park. Be aware that the sites are non-electric. There is a dump station located in the camp.
Reservations for Carolina Beach State Park (and many others in North Carolina) can be made at the following site:
http://www.reserveamerica.com/camping/carolina-beach-state-park/r/campgroundDetails.do?contractCode=NC&parkId=552806