It looks like a six cylinder Holden Torana with a different grille. Knowing that South African customers like bigger engines than Vauxhall would supply, I'd guess they wanted the long nose torana. Then it would likely be called a Ranger.
However then I noticed the left hand drive, so it might be Korean. Found it,
It's the Chevrolet 1700 made by Daewoo predecessor Saehan Motors.