Hi, there are quite a few of the Elstob book on UK and US Alibris? Dunno what postage is like to SA, though.
https://www.alibris.co.uk/Warriors-for-the-Working-Day-Peter-Elstob/book/7123954?matches=5
https://www.alibris.co.uk/Warriors-for-the-Working-Day-Peter-Elstob/book/7123954?matches=5