Automatic transmission

Hi guys, can anyone give me a nudge in the right direction for an auto transmission for my 2004 E46 320i? I've tried unsuccessfully BM Spares and Peninsula BMW both in Melbourne. I am, as my user name suggests from Tasmania and there aren't too many options down here. The BMW service guy quoted $2000 plus fluids, fitting etc for a second hand one or $6000 new. My only other option is to buy a complete damaged E46 and part it out but that's too complicated right now.

Any help would be very much appreciated.