Please refer to Colin Owen in his book under Collar Badge No.1018.

Sadly we only have one of these Collars.......facing to the RIGHT then it would have almost certainly been worn on the Right Hand Side......facing inwards.
"Quartermaster's Comment":-  There cannot be very many badges around for the Regiment De La Rey..........ONS WAARSKU......was worn around 1964 through until 2000. It has 'Pin' Fittings.