I was asked an interesting question yesterday concerning availability of INTAF 20mm figures on the market. I suggested using the Underfire Miniatures range which have some good figures in the Rhodesian Home Front range which could double for INTAF figures.
A bit of cutting and changing of heads and you could have a reasonable batch of 20mm figures for Intaf.
Elheim miniatures do 20mm heads with the floppy hat for the conversion and Early War Miniatures do KAR separate heads with slouch hats.
The INTAF MRU (Mobile Re enforcement Unit) can be created by just using the RAR figures as they wore standard infantry kit.