I realize I'm rather late to the conversation here, but I want to add that in addition to the equipment mentioned above there are also a noteworthy trio of truly ancient 42" gauge Porter 2-6-0s preserved in Japanese collections:
Hokkaido Tanko #1 (C/N 368, 1880) is on display in Osaka.
Hokkaido Tanko #2 (C/N 369, 1880), formerly at the Tokyo Transport Museum, is now reported to be at the new railway museum in Saitama.
Hokkaido Tanko #6 (C/N 672, 1884) is on display in Temiya, Hokkaido.
This is what we're talking about: Hokkaido Tanko #2 in Tokyo
It's true that they never operated in the US, but they're American-built to an American design, and represent the last survivors of one of H. K. Porter's most popular early models. (Porter was the first American locomotive builder to export to Japan.)
-Philip Marshall
Edited 4 time(s). Last edit at 10/27/2014 06:15PM by philip.marshall.