kori, things turn up all over the place in small numbers. I think the Iron Horse engines were rather uncommon in Australia - there were certainly some in New Zealand though. If you look at this thread you can see the story of a restoration on one:
https://www.outdoorking-forum.com.au/forum/ubbthreads.php?ubb=showflat&Number=19752

That is one of our most popular threads.