This may be useless trivia or perhaps a back door to further info.

Here is a site that has paint chips for General Motors Holden (GMH) which you know is an Australian company.

http://www.fefcholden.org.au/techinfo/gmhpaintnumbers.html

There is a listing 7447 which is Breton Blue in 1956.

Others will know far more than I the connections between the different GM companies and their histories.

"Nothing astonishes men so much as common sense and plain dealing." - Ralph Waldo Emerson