On a very rewarding trip to Australia March 2010 we came by car from Adelaide and the 1st night stayed in Port Augusta. This drive is of course a bit of a drive but smooth fast road. If you are thinking of going to the Port Augusta area for some reason my trip was through the wine country then down the steep pass towards the freeway that leads to Port Augusta.
I could not resist (1st night out there) so took binoculars back up after we settled in to our motel and went to a dirt parking lot that has a monument I think to John Horrocks if I recall. This lot is very close to the point where it drops off down the range towards Port Augusta as I recall. I bet observers in that area are likely to know about that place.
The site has around an 8 degree south horizon that rises to about 20 degrees to the south east (my estimate in notes). My sqm meter was back at the hotel so I only guessed at my NELM (using known stars) to be at least 6.3 but I suspect a little better.
The lot is mostly on a slight angle but I felt it had enough 'almost flat' space where you may need a slight wedge for a dob but tripods would be fine. It has some altitude there with not much nearby city lights. If I lived in Port Augusta that would likely be a fine choice at only 30km drive for ease of access and darkness. It is a very nice road along the ocean from Adelaide but it would of course take some hours to get there.
We then went on to Arkaroola and as you said, mighty nice. I was in heaven for 5 nights from 21.5 to 21.7 sqm nights with full usage all by myself of the observatory owned by Doug Sprigg's (a wonderful host to be sure). 5 stars for the resort there if you like astronomy and/or outdoor life in that wonderful Flinders range area.
I do miss those great sights you all have down there