Should anyone be interested, there is a pewter and brass kit in HO scale for these locomotives, made in England. This site has photos, plus others of Alaska RR prototypes:

http://www.roundhousehobbies.com/steam.htm

There are links to a few more photos of S160s in Alaska (including extant 557) on this page, under the 714th ROB titles:

http://alaskarails.org/ARR-history-main.html