Hi Kirk,
...getting my hornstuff from Nick Nguyen for years now (find him on facebook). Very reliable supplier. He runs a big Waterbuffalo Farm in Vietnam where they are crafting all sorts of things from horn (look up pufacraft). You also get flattened and hot pressed hornstrips that are easy to work with. It's much cheaper than the etsy stuff also. To get what you want its very important to make very clear what you want, then you get what you want.
Cheers