Mike - I'd try using a pure sine wave inverter (rather than a cheaper modified sine) off your car battery or another 12v power source that you might have access to.
Here's a 300w unit from Tricky's for $144 that'd do the job admirably (plus you can use it for plenty of other things such as charging your phone or whatever other 240v appliances you have):
http://www.dse.com.au/cgi-bin/dse.st...uct/View/M5113