I should say that I am a UK qualified solicitor, not a Australian lawyer and there are no Australian solicitors. However I think I can point you in the right direction.
I believe that he will have to apply for a Working Holiday Visa which will permit him to travel to Australia and work for a period of 12 months. He would have to apply for this to the Australian High Commission in London or make the application online.
He can do any work in Australia but must not stay with any one employer for more than 6 months.
He must have health insurance, may have to undergo a medical examination to confirm he is in good health, provide a police certificate confirming no convictions and have funds in place to cover his stay (generally $5000.00 Australian dollars is sufficient (about £3034.42 on today's exchange rate)).
He can contact the Australian High Commission in London for further details:-
Australian High Commission
London WC2B 4LA
(corner of the Aldwych and the Strand. Nearest Tube station: Temple)
Tel:(NNN) NNN-NNNN4334; Fax:(NNN) NNN-NNNN5333
You can obtain visitor's visas based on family there but not initially for the length of his intended stay and he would not be able to work.
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