Not wanting to rain on your parade - it's one very nice horn, but it looks as though it may have been re lacquered in the past. I say this because the engraving looks a little faint in the last picture and there appears to be tarnish and even finger (or hand) prints under the lacquer. Also, the engraving seems to be under the lacquer rather than through it, as it was on American finished horns.
I only mention this because it does affect the value, and if I think it my be a re lacquer then the chances are that someone else will too!
I only mention this because it does affect the value, and if I think it my be a re lacquer then the chances are that someone else will too!