I mentioned the Rostyle rim to a rooinek buddy of mine and he said he knows them. I thought, yes, that's because he has lived in South Africa. But no, he said...

I do know that in South africa, they don't only appear on ACVWs, but also on Ford Escorts and Ford Cortinas, so not only are they not unique to ACVWs, they are also not unique to South Africa.
Rubery-Owen-style (Rostyle) rims are a British product (Rubery being a suburb of Birmingham, Birmingham being the home of Rover, Land Rover, MG and a host of other British cars) In Britain and Europe, Rostyles have been sold as standard rims on MGs, Truimphs, Land Rovers, Ford Cortinas, Capris, Anglias, Minis, and Opel GTs and Mantas.
I'm sure someone manufactured them under licence in SA somewhere, probably PE, to support the SA motor car industry.