This tells it all here. You can remove the currency selectors in the templates uploadproduct etc.
Then as the code suggests if currency is empty then it shows your global option.
If you set in Admin => Global Options the currency to the australian symbol it will show
Content visible to verified customers only.
Basically all you want to do is make sure your Admin => Global Options and Admin => Payment Options currency variables is set to nothing since there is no such thing as an australian currency symbol