MilSims is very nearly the
only game store in Australia currently selling historical wargames of any sort. (I know that it's not the
only one, but close ....)
www.milsims.com.au
MilSims used to sell CH stuff (and possibly still have some of it that they can't get rid of) but not other 3rd-party stuff, but they are under new management now so I can't speak for their current policies, other than they have stated that they will stock official ASL products (and other MMP games).
(There are quite a few stores around the country that sell boardgames, but most of them stick to the "family" or "Euro" style games, along with collectible-component games and the like, which may have military themes but are not "traditional" wargames.)