Worth a chat
These guys are over in Lismore (nearly the exact opposite side of Australia from Perth) Australian Motorcycle Tours
but they would be worth a chat. They will do a deal of 9,600 or something for the full kit, and then give back $7,600 when you get it back within 3 months or so.
If you are after a DR650 or something similar, they are a little like hens teeth at the moment over here in Perth 2nd hand - I know I have been looking for one!
If you can get out to Midlands there are a collection of dealers, but that will take you out a bit. Next stop might be Victoria Park and Dale Britton Motorcycles on teh Albany Hwy. I actually have a test ride booked with them for a '07 Tiger 1050 tomorrow, but haven't ever dealt with them before. There are a couple of other dealers as well around them.
Next stop would be the 'quokka'. Classifieds by Quokka Online
This hard to use and old fashioned website is the best thing you will find to a trading post that services the Perth area, and is the Paper/online sale point most used by West Australian's.
Hope that helps,
Stop talking, its time for action...