Yep Canon in Sydney is where you want to head...
Unlike their offices in Melbourne, their camera repair centre is in Sydney.
If you head to Melbourne, i've get my canons serviced at Camera clinic in Easey st in Collingwood, they are great and have built custom solutions for us as well as taken apart all of our Nikon 600mF4's to replace the VR and reinforced the shutter on our D3x's. Highly recommended.
5dMk3 (x2), 5dMk2, 7d, 550d, 16-35 f2.8L 24-70 f2.8L, 24-105 f4L, 70-200 f2.8L, 28-300m L, 50 f1.2L, 24 TSE L, 90 TSE, 8-15 Fisheye F4L, 100 f2.8L Macro, Fuji x100 + stupid amounts of video & studio gear. Addicted to buying toys.