Hey Mr Kaz,
In 'those days',
I used to carry a 'Lions' Christmas cake in the back at ALL times, as well as a foam Esky drink bottle full of water - hopefully it would not break 'on impact'.
(Small 'Chully Bun' type to friends 'Very East'....)
Also had a medical kit put together by RFDS Doc of some fame in WA.
Never had to use either - thankfully.
Worked out of Carnarvon for a while, then Yaleen & out of Hedland, Tom Price etc etc.
Good country if you 'respect it'.
I still carry a 'Lions' Christmas fruit cake 'in the back', no, not the same one....but I reckon it will help me to last about a week.
Cheers