Try Speak Creek. It's just south east of Port Augusta and close to Wilmington. Right on the base of the Flinders ranges. There is great fishing around Port Augusta and the Speak Creek Caravan Park is natural bush. They have powered and non powered sites. It is just paradise!
I have been there twice now and I will be back.
Any man, in the right situation, is capable of murder. But not any man is capable of being a good camper. So, murder and camping are not as similar as you might think.