I'm not really sure how suitable they are for Australian use, and I'm a bit confused at what I'm looking at on their page.
https://www.fjallasport.is/product/suzuki-jimny-33-35/They seem to offer these, which are barely wider/bigger than stock:

Or these, which are enormous

But they're all fibreglass. fibreglass is fine for snow where they're not getting knocked into things but for use on tracks they're going to be vulnerable.
And 1000 Euro + shipping+GST
Golly.