The absolute place in Australia (I just completed the big lap - circumnavigation in our RV) is in Melbourne. While there I played all sorts of boutique guitars you only read about in magazines and forums, Bourgeois, Santa Cruz, etc. I visited there twice in two days and would have played something like $125,000 worth of guitars.
If you choose to go to Melbourne another great guitar related experience is a tour of the Cole Clark factory. So very worth it.
I’m from near the southern area of Queensland, can give you details on a variety of guitar shops there if interested.