This horn may have been made in Australia. When I see "different" horns that are a little hard to place, its major figures can often tell us about its origin. Also seems to be more common on British Commonwealth horns to have a mechanical/adjustable spout. The curvature of the horn body is an almost perfect match between the body and the section above the lower band. That, along with a matching band near the spout end that is very similar to the lower band, suggests to me it is a solid horn with two carved/added bands. The lower band was probably carved to hide the transition/intersection better between faceted and round surfaces. This horn has enough "different" details that I do not think it is American, and the kangaroo tips it toward Australia. Australia was also known for its "rough and tumble" men, many convicts released there, that the "tough guy" figure seems to support. The slightly recessed plug [flat?] and scalloped end tends to support this attribution as well. The Australian horns I've seen do not use softwood/pine butt plugs, as New England horns most often do, so It would be nice to see the plug.
Can we see a picture of the plug?
Shelby Gallien