Nice little horn with some interesting engraving. Cork is not unheard of for end plugs especially for salt horns or horn containers not heavily used. This is the first powder horn I have seen with a cork end, however. Rather unique, I would say. The holes are unfortunate, but are all too common as the beetles seem to be almost everywhere.
I have always thought that dental bonding material could be used to close up small to large holes. It can be easily shaped and colored to whatever is called for. It hardens to about the same density as the horn itself. I have suggested this to some horn restorers, but they all seem to prefer other substances. Kits are available at dental supply houses if anyone wants to give it a try. Let us know how it works, if you please.
Dick