Quote Alex Mc="Alex Mc"Hull had a south african winger i think, cant remember his name though.'"
You might be thinking of Wilf Rosenberg ('The Flying Dentist'). I think he played for Leeds as well.
There were a few South Africans came over in the 1950s and 1960s : Tom van Vollenhoven and Len Killeen at Saints, Jan Prinsloo at Saints and Wakey, Alan Skene and Gert Coetzer also at Wakey, Fred Griffiths at Wigan, Piet Pretorius at Worky, not to mention some Rhodesians (as they were called then) - Johnny Gaydon at Saints and Widnes and Trevor Lake and John Winton at Wigan. Not 100% sure of the last couple, since this is all from memory
Going back even further there was George van Rooyen, the only non-local in the Widnes cup-winning team of 1930. He also played for Wigan, as did Attie van Heerden around the same time I think.