Thank you to Ruskie, Leanne, phenolphthalein & Jim1 for your input.
I had already contacted Whitehead Studios and have now sent off to John Oxley Library in Brisbane with a copy of the photo for their advice.
Can't really provide a better image as it was a photo taken of a photo seen in a shop (with permission), so it is just as it came from the shot.
At the time I hadn't considered looking into it too much as I was hoping the person who first showed me the image would be able to shed light on its background.
I almost feel it will turn out to have nothing to do with my family, but it's a case of doing some negative research which just could turn out to be positive.
So will wait to hear from the Studio and the Library.
Thanks again for suggestions.
Barb