I am going to hazard a guess that gun passed thru Japan prior to WW I and the 'custom' work including the gold plating was done there and at that time. I saw a SAA that looked very much like this one in either 1958 or 1959 while working at a Reno Gun Shop. I bet that someone had that work done and the SAA eventually wound up in Europe. The quality of Japanese engraving has gotten much better over the years after WW I. ............ Big Cholla