JIM (Japanese Invasion Money) in the 1950' and 60's was very common, you could get it in Australia by the shoebox full and because of residual negative sentiment against the Japanese, was very lowly regarded and considered worthless. The negative sentiments have long since disappeared, but unfortunately the notes these days are very rarely found in bulk. American servicemen took loads of them back to the 'States after their tour of duty finished and they were demobbed, and the same story is true of the Australian situation. I have very good booklet was written by Arlie are Slabaugh publ. Chigago 4th ed. 1971, by Hewitt Bros. As you are probably aware, some of the items pictured can be pricey these days. A regular supply of more common single notes can still be obtained in dealer's junk boxes I have about 30 different examples, including the brown 10 shillings of Oceania. Interestingly, the replica one pound can bring quite a bit of money.