Country specific Block list (Australia)

No, I have not seen any AU specific lists. It's possible to find out where the ads originate from and add them to pi-hole. You could also backup your custom lists via Pi-hole Teleporter so that your findings are not lost.
How do I determine what domain an ad is coming from? - FAQs - Pi-hole Userspace

Pi-hole comes with ad-lists that are not enabled. How do I add additional block lists to Pi-hole? - FAQs - Pi-hole Userspace Also you'll find more lists here http://v.firebog.net/hosts/ and https://wally3k.github.io/
The problem adding more and more lists is the risk of false positives. Better to stick with pi-hole defaults and widely used block-lists.