Our average local bottle store sells a fairly good variety of beer that costs about R130 for a case of 24. That obviously excludes expensive beers imported from Belgium or Germany - those easily cost R350 for a case of 24!
I guess it's clear that one can't simply convert AUD, GBP, or EUR to ZAR to compare - but it would be interesting to know how much locally brewed beer costs in various countries. Leave a comment on this post, and let's see if we're as lucky as our Australian family thinks we are. :)
To easily convert your currency to ZAR, try using Google.
For example, do a search for "20 GBP in ZAR".