Maybe a Cub or Pioneer hardfloor second hand would be - for that price - your closest bet if you're looking for a hard floor Aussie built.
Of course there is the Jayco range of wind up campers.
Otherwise soft floor you'll have much more choice in that price range.
There are more but Aussie brands but the main ones I know of include Vacation (I'm bias - obviously), Trackabout, Customline, Complete Campsite, Mountain Trail, Jimboomba, Lifestyle, Modcon off the top of my head.
Welcome to Myswag - will be interesting to see what you do...
McT