Well it certainly is a beautiful gun. Japanese? English Best Maker? Even if by some twist of fate that were the case, without the appropriate markings the gun might as well be Japanese. I do agree that the engravings appear to be by hand, due to the slight lack in uniformity. If someone bought a Webley & Scott out the back door of the factory, and somehow it went out missing the makers mark - it would never be viewed by the market as a Webley & Scott even though the original buyer would know that to be the case.

Did the fellow in Japan tell you WHY he thought the gun was of that particular gun house? Specific markings? Surely his guess was based on more than general appearance.