Robert Heinlein recorded in Sydney

I received an interesting email from Bill Patterson editor of The Heinlein Journal, of The Heinlein Society: "In February 1954 Robert and Virignia Heinlein came to Brisbane, Australia and made their way to Sydney where they stayed for approximately two weeks, partly for tourist purposes, partly to investigate a piracy of "Life-Line" (that turned out to be a piracy of his American publisher, Shasta, rather than a piracy on the part of the Australian publisher, who had put the story out as a small paperback -- a very rare item, indeed, if you happen to own it). While in Sydney, he was contacted by the local SF club, The Futurian Society, and apparently gave a speech to them one Thursday evening.in "the club room." A Brian Finch wrote thanking him for that talk. In June, there are two letters from "Vol and Laura" (no last names) saying they had heard a taped message he had recorded for the then-recent convention in Sydney. I am trying to find out whether that tape recording (possibly it was a wire recording at that time) still exists in original or in some form of transcript." Does anyone know about this tape recording? Please let us know!