Airstream will not build an Australian version with 230 volt.
Your only option would be to either import just a shell and outfit it in Australia to Australian code, OR import a US 120 volt version and use step down converters to control voltage. You would have to contact your customs to see if they would allow a 120 volt trailer into the country.....I highly doubt it.
Remember to buy any 120 volt appliances you wish to use, when you buy the trailer for use in Australia.
Per Mare, Per Terram and may all your campaigns be successful.
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