Very nice horn with interesting work. Since I focus on Midwestern horns, I am only speculating on this one. The small images of a winged "$#*! horse" [the system refuses to accept the first word, "7734" inverted, and replaces with symbols] and a mermaid/siren with lantern suggest an eastern horn, as does what seems to be a soft wood plug. I can see why you like this one, well covered and interesting images... and a name to research.
I'm probably out in left field on this one, but the rectangle with angles lines and numbered banner reminds me of a couple early "developmental" Tansel horns by the sons, probably done when first starting to carve and before they had fully developed their carving skills. A couple such horns have small areas of "practice" work, often with letters or numbers or small "pieces" of images, that [to me] suggest it was done before carving the more important figures on the horn that used some of those numbers, letters, or line styles.
Shelby Gallien