Sometimes people's inability to even consider helping themselves is beyond belief.
Do a Google search for "rewireable australian plug" - you should find a good few that you can fit to the existing cable. A word of caution based on your asking the question you did: Get someone COMPETENT to change the plug.
Manuals are a little trickier, although you COULD try contacting Breville and asking. (Is searching for Breville's website beyond you?)
I got one vaguely promising result, although you will need to email the chap: