Sample 1:

Very similar to Rhodesian version, but thicker canvas and much more padding around shoulders.  Pouch closures are wood toggle loop, like chicom chest rig but with synthetic rope type closures.  These vests were likely used before the nylon Niemoller equipment.

On 1st Pattern Recce Jacket:

This vest was very similar to the one used by 32 Battalion from 1979 – 1981 though the one pictured below is more similar to the Rhodesian fireforce vest.

From http://www.32battalion.net/32%20Battalion%20Equipment.htm.

Usage Photos:

Vest seems to have been used by 31BN (Bushmen) of SWATF (South West Africa Territorial Force).  

Comparison with Rhodesian Fireforce Vest:

The SADF version clearly shows the Rhodesian influence in color and layout although the South African canvas is a lot heavier than the Rhodesian material.