Graaff-Reinet is the gateway: Cape Dutch gables, the Valley of Desolation at sunset, and mohair country all around.
Go in shearing season if you can, and ask locally about farm visits. Buy one finished mohair piece made in South Africa — a scarf, a throw — and you’ll have closed the loop in a small way.
Come home with dust on your shoes and a better question about every label you read.