Owen,
At:
[www.sunsteam.org.au]
there is a list showing the disposition of the 793 MacArthur design 2-8-2 locomotives produced. Some were built as late as 1948. As far as I know, other than the one 42" operational with the QRy, there are two ex WP&YR 36" USA 190 & USA 192 operating in Tennessee [Dollywood] and N. Carolina [ET&WNC], and one 1000mm operating with the Northwest Frontier Ry in India.