Mate,
I dont know if any car hire place.
But here in oz we need to apply for international drivers licence which is ok to use in LOS along with your oz licence subject to it being valid. i think only costs $33 and is valid for a year. You may want to query this from the UK roads authority (vic roads in oz) they will be able to direct you. I ampretty sure that the international DL is also applicable from the UK.
Maybe UK BM's can shet some more light on this
Not much help i know - but that's my 2 bob worth