I had a similar issue once, if you are game to purchase one overseas (I'm in Australia also) You can purchase one for about $165 US online, about $330 Aussie dollars. Allow $40 for posting and you'll save a good hundred dollars or so. Check out http://www.pricewatch.com
Hope this helps.
 Prices are cheaper than what I thought, $118US for an Abit one.
Also check out the Radeon 8500 $126US