It is unusual in art commentary to include "best", "sought after", "top quality limited edition". and "sale" in the same breath.
The very very best are unlikely to play the art-commodity market game and as for "limited edition" product this is arguably inferior to the grand singular original piece. From a collector's point of view I won't touch limited editions. It does not enhance my joy in possessing a valuable work to know there are a dozen more or a hundred more exactly like it out there somewhere.
A place to delve into the stratosphere of Australian photography (real photography, no ink-jets, strictly APUG style) could be Point Light Gallery in Sydney. The director Gordon Undy is famous for expensive and very expensive platinotypes and his eye in selecting photographers, Australian and foreign, has been pretty consistent for many years.
A venue at the other end of the scale could be the Queensland Centre for Photography in Brisbane. This place will hang anything with a "photo" echo, ink-jets, editions, colorful bacteria, whatever passes muster in this mad mad post-modern world.
An island of dispassionate scholarship on photography should be the collection of the Australian National Gallery in Canberra. But the identification of photographic worth is controversial even here. Virtually none of their "contemporary " holdings would qualify for the walls of Point Light Gallery and the old stuff, Dupain, Kauffmann, Bostock, and the like wouldn't get much of a run in Brisbane.