That is a nice hat, especially with the provenance. All of the Commonwealth or Empire clothing and equipment was suppose to be interchangeable. As we all known there were distinct manufacturing differences between countries which means that you can tell from which country the person is from just by the cut and manufacture of the uniform. Canada tried as much as possible to keep Canadians clothed in items manufactured in Canada although this was not possible all the time as the supply system, as in the case of the Italian theatre, may be dispensing Indian made kit to Canadians in the 8th Army or specialist kit like jungle clothing, which was not manufactured in Canada, would have be drawn from stores once in theatre. Commonwealth Air Training Plan personnel in Canada were issued Canadian manufactured winter clothing and RN personnel could draw RCN clothing from stores in Halifax so the system worked both ways. The joy of all of this is that in the case of your Australian manufactured Bush Hat, there are some nice foreign manufactured pieces out there with links to Canadian.