https://www.cams.com.au/get-involved.../licence-types
^^Try that, see how you go. The first link in the list is the renewal but it's unclear whether you are good to go straight away. Some shit about having to pay an extra $75 if you want the licence within 5 days etc.. Maybe I am reading it wrong. Try calling Jurgen or Ben at Mc's maybe?
I'm pretty sure you can purchase a day licence at the venue.