that looks like a US Hobbies box. The white printed sticker was not used by either US Hobbies or Westside that I am aware of.
the number on the box should be the serial number engraved on the bottom of the frame of the locomotive. That silver/red sticker does look like USH.
By the way, the original boxes on USH stuff had a large label similar to the one with the number. They would state the class also as L4b or L2 or whatever.
If the locomotive had a plate on the bottom stating it was built by KTM, that should be sufficient. It does not really matter about the importer.
As I stated above, in my definitely limited experience, US Hobbies imported 2 different versions of NYC 4-8-2s and Westside never did one.
