PTA is cheap, very cheap!
In Potchefstroom, only about 200km from PTA we pay 3 times more for vaccines.
The most expensive one is for the Rhotavirus, it is combined with some other stuff but that one worked out close to R1k. I would recommend getting it though, out first child had that virus and it was scary, her tummy went so much that the hospital later did not even bother with nappies, they just lay her down on a towel. 2 weeks of non stop diarrhoea.
Vaccines is also getting very scarce, we had to wait a couple of months for one of the vaccines for our youngest.
Around 2 years ago the government messed up bad with the importing of vaccines and the stock were depleted for months. As far as I could gather a private institute may not import vaccines, it has to go through the Department of Health, or that was the story they gave us, and then the government hospitals and clinics gets issued first.