I don’t know how and where records are kept in Australia, but if they have court houses in each province it should be simple to go there and ask to search the books for records of a relative, etc. and see if the numbers match for 64. Naturalman should take a trip to S.A. court of records.
Adelaide (the capital of South Australia) is about 500 miles from where I live.
The registry would be kept at one of their central archives and you would only be allowed to check a record from the period of question if it was your own record or that of a dependent.