I'm busy researching all flight gear used by the SAAF, such as helmets, masks, flight suits, life preservers, survival vests, shoes, gloves, etc.
However, I also have a very small collection which I'm trying to build up.
Herewith early SAAF helmets:
The first hard helmet used by the SAAF, the British Helmet Mk1 (no visor). It is used in conjunction with the inner liner Type G (with earphones) and Type H oxygen mask.

Next up is the Helmet Mk1A (M) (With visor). Earlier Mk1s without visor were upgraded to this standard.

Initial Buccaneer used the Helmet MkII, which I'd love to acquire.
The Helmet MkIIIA (with throat mike) was used by Flight Engineers for rescue work. I hope to acquire a MkIIIA with boom mike.

Helmet MkIIIB with Q2A oxygen mask:

Leather flying helmet With Gosport Tubes (circa 1939), used by Capt. Theo Purchase to train SAAF pilots on the Hawker Fury and Hart prior to flying Marauders in North Africa:

Leather helmet with RAF Mk VIII goggle replica and Impala MkII Helmet MkIIIB:

I've just acquired a Gueneau 316 helmet with boom mike, but it is missing the visors and visor mechanism. In the process of attempting to purchase spares from France.