Mate, I think you’re confusing a lot of people here with terms like part
91/125/131. They don’t exist in Australia.
The most important thing is you need residency and the right to work here.
As far as hours go you only need to meet the minimums listed for recruitment (500 PIC or 300 Multi engine PIC or 150 PIC/100 ICUS/1500 Turbine FO) to apply. Even though it is the most common path you don’t necessarily need to have flown for a regional airline prior to joining mainline. In fact in Australian pilots have gone from flying C172/182/206s in charter jobs, or instructing on C172s directly to mainline jobs on 787/330s.