I made one taking one of the old lances that was mal-formed. I removed the lance from both side of the hands. Took the upper lance cut it part way up to make the wide end as the mouth of a horn. Raised the bent arm up and reversed the part of the lance I cut and pinned it to the bottom of the hand. For the top of the hand I added some brass wire that was thicker, only a few millimetres long and pinned that to the top of the hand and added so green-stuff to make the mouth piece. Now I had a trumpeter ready to blow his horn.

Hope that helps,