WARNING!
Be careful it's not a 'gray market' lens which means Canon Australia won't touch it under warranty if anything goes wrong!
I know not much does go wrong with L Series lenses, but you need to ask the supplier whether they're covered by a Canon Australia warranty and, if not, ask yourself whether it's worth the risk for the sake of ~$500.
There are online retailers of Canon lenses too. Here's a couple of links...
Quality Camera Sales - a bit expensive compared to others but VERY good service and ONLY sells Canon -
http://www.qualitycamera.com.au/prod...&products_id=8
Cameras Direct - some gray market gear so best to check -
https://www.camerasdirect.com.au/ind...6l-is-usm.html
DCW - again, some gray market gear here too, but they have a shopfront in Sydney -
https://www.camerasdirect.com.au/ind...6l-is-usm.html
Have you considered a 70-200 f2.8L (non IS) plus a 1.4x or 2x extender? For a similar price you'll get far more flexibility!
Good luck.