Yep, realised after I posted that it was in the wrong spot - sorry about that. Ended up staying at Pondalowie ($16 a night vs $6 for the other sites) it had toilets with a small (close to empty) rainwater tank. 30 second drive to the beach which sounds lazy but given you can drive onto the beach without deflating tyres, I had a wife two kids and beach stuff to move, I had a few beers in the fridge and cricket on the radio (shame about the result!) it was magnificent! Saw lots of snakes on the road (dead and alive) but none in the campground but thanks for the heads up.
It was a great place and Rhinos Tavern, which is inside the national park served good food, cold beer and cheap fuel.