Finally ...
WB638 (C1-0081) - VH-BUR and WB639 (C1-0082) - VH-RNF ... as I can't be quite sure your Mum's F414 records an 8 or 9. Both these airframes were lost whilst on the Australian Civil Register in 1957 and 1961 respectively. WB638 was a Spinning incident and WB639 was an EFATO. Perhaps our good friend Dora-9 who is a renowned authority on Australian Chipmunks, knows more here.
WP796 (C1-0688) - Variously VR-NBK, 5N-AAG and ZS-CHP went to Nigeria in the first instance after disposal by the RAF but appears to be still airworthy under the South African Civil Registration ZS-CHP and based in Stellenbosch SA. Unfortunately I've been unable to trace a current picture for you.
I hope the above has been of some interest to you ... hopefully your Mum will be pleased to see that the majority of airframes she flew are still flying !!!
Let me know if I can help further ...
Best regards ...
Coff.
Last edited by CoffmanStarter; 5th Oct 2015 at 06:29.