FInd a good import agent (that is the key to a low stress import, they know all the right people to get your car out of customs), I use a Guy here in WA that does not BS you into thinking it costs heaps.... A kit from the States should cost you no more than 10k landed and cleared at your house. I'm not sure about SA but it is a direct link to Oz not via Singapore from the States.
I am also looking at CAV at the moment so will know more soon.
You bring the car in as parts....not SEVS or anything else, then you build the car as an ICV......it's all easy. I helped a Mate bring in a kit from FFR into WA and it was all pretty straight forward. I had no problem bringing in my FFR or registering it.
PM me and I'll send you some contacts and more info.