Thanks for the welcome Dick.
As I said, the pump looks identical in every way except for the slight difference in the colour scheme. Mine has the dual bottles and all.
I spoke to a dealer in memorabilia here in Aus and he told me that these things are very common and you can buy reproduction ones at all the swap meets for a few dollars. Given mine is at least 30 years old (I was about 7 or 8 when Dad gave me a smack for taking it to school to it must be at least that old!!) I doubt mine is a fake but the colour scheme variation has got me curious.
I'll post the piccies in a couple of hours when I get home from work.
PS - it's about 105F in the shade here today - so much for a cool Christmas!