You might be in luck, had a look at the LBA (German version of the CASA) they do have a Type certificate Data Sheet for the AN2 TCDS-No. 2069 Antonov An-2 PZL-MIELEC (Polen) An-2 / An-2T 8 (3/00), would need to see if CASA would then issue a CofA on the basis of the LBA TCDS.
If they will, the aircraft would need to registered in Germany first, or buy one of the ones already registered there, and export it to Australia.