Paul,
Have a look at
http://www.mheaust.com.au/Aust/Austindex.htm
This gem is contained in the text -
"This Australian Olive Drab colour has been used since 1967 on Australian military vehicles"
So you guessed right, if the author of MHE is right !
Although I can't point to any authority, I don't think the 106mm RCL carriers, were ever painted anything but lustreless green. Those that remained in service in the late 80s/early 90s may have got the cam job, but as far as I know they were never Bronze Green.
Jack