I'm not particularly interested in starting a double-dipping spree on these until I can get an Ultimate Edition of Philosopher's Stone with the original title.
Alternatively, you can still get the Australian Ultimate Edition of Philosopher's Stone, but it's $90 and I'm not sure whether any material is in PAL format.
Final option: buy the USA Ultimate Edition and the Australian Collectors Edition and swap the discs (and live with Sorcerer's packaging labeling).
IMO, Warner will not release any more Philosopher's Ultimate Editions (like for the UK), but will concentrate on Collectors Editions. I suspect Australia will not see any more Ultimate Editions apart from the first 2 as I don't think they are selling well enough for Warner to spend money on further special Region B editions.