Australia's fighter problem was industrial and geographic

Why did Australia not build Hurricanes or Spitfires for home defense before the Pacific War?

Australia had a smaller aircraft-industrial base, relied on imported types while developing local capacity, and needed longer-ranged aircraft better suited to Pacific distances.

Australia lacked Canada's depth of aircraft-manufacturing industry and therefore depended more heavily on imports and a developing local base. Hurricanes and Spitfires were short-range European interceptors, so they were not automatically ideal for Pacific distances; the same range problem affected British bomber designs such as Lancaster. American delivery routes and aircraft offered a more practical source of reinforcement than simply transplanting a British production program.