Air Freight?
The problem with having bags heavier than 32 kgs is that due to OH&S regulations the airlines won't touch it as checked luggage. Seeing recent developments I wouldn't be surprised if that dropped to 23 kg sometime in the near future.
Air Freight is slightly different in that most of the time they load containers that go onto the plane. Only issue with Air Freight is that they will charge based on cubic volume weight or actual weight, which ever is higher.
Another option is using a freight company that specialises in events freight. They will make sure it gets there on-time and intact. On company I have worked with in the past is Show Freight (
www.showgroup.com.au/freight/).
Otherwise call Virgin / Qantas. They will be able to provide you with a quote for freight. Another option is Australian Air Express.