Sorry Ian, my clumsy cut and paste - no, they do a thing called a "billet bar end adapter" which then goes into the end of the handlebar and expands with a wedge on a shaft, this leaves a small diameter channel outside the end of the bar to which you then fit the mirror.
Here you go, my bike with the mirror fitted from the Forum:
http://www.vincentownersclub.co.uk/...-from-this-years-manx-grand-prix-2010/cat/787
The end bar adapters are available seperately on that website.
CRC is the manufacturer from memory, you can see all their products on the web, they are based in California from memory and list worldwide distributors so you may find someone local to you.
http://www.constructorsrg.com/mirrors/hindsight.html
They don't show an Australian importer but if you struggle to get them from anywhere let me know and I can get them and post them to you in the UK.
I found them very helpful and they posted me some shouldered allen screws when I stripped one.
Hope that makes sense, I will have a look on the Forum and see if I can find a picture of my bike with the mirror.
Best of luck.
Stuart