Yeah, there has been a bit of discussion about this bird on ZooChat before, and it isn't a pure muticus. Melbourne Zoo do have a sign on its aviary identifying it as a green peafowl, but on their census it is listed as a hybrid (Pavo sp.).
Apparently there are green peafowl in the region, both Adelaide Zoo and Gorge Wildlife Park keep them, but not in any great number, The population is thought to have few founders and be showing signs of inbreeding issues.
Hybrids between the two Pavo species are fully fertile, to the extent that a stable, true-breeding hybrid exists, known as Spalding's Peafowl, originating from a Green x Black-shouldered cross. One of the three muticus races [Burmese?] is rather more blueish green, but I would agree that this one is not pure bred.
I second FBBird. This is a Spalding peacock. I don't think there are many pure green peafowl in Australia, and I know they have issues getting animals into Australia because of specific regulations.
unfortunately, these birds, like so many other birds go out of *fashion* and the birds are lost to aviculture, to many species here in Australia are now unavailable for that saw reason,