Horns are not of ample supply as they were around here. We have a small community con flab once a year on one of the homesteads. This year I saw gourds, wooden, some leather covered powder containers, even one plastic bottle covered with rat hide. I know it doesn't seem authentic, especially the plastic, but I only know what I see in old linotypes and read what was supposed to be authentic, I wasn't there. I like the out of the box, homemade solutions to problems, sure some are very crude, but functionable. My first powder horn was one I got at a local butcher shop, not really exceptional, but worthy. I finished it down with a broken glass scraper from an old fruit jar and a borrowed drill, carved the plugs with a Barlow knife ( that was back when they were actually Barlow's).
I have hardly found any store bought horn or other accruements that I want because of looky. That being said, there is some beautiful work that comes out of the store and craftsman's shop, but if I were to purchase a scrimshawed horn or a finely decorated bag, I would feel like it was a personal art that really wasn't my own. However crude my own would be. If a person can't find what they are looking for at the moment, finagle something else to serve the purpose and fine tune it with practical use until something better comes around, such as that perfect horn.
My most humble apologies if my opinion offended anyone.