I think the serial number on the 19-4 starts 61K, but wouldn't swear to it based on that photo. If so, it's likely to be a 1979 product.

On engravers, permit me to make up a rule: Engravers don't usually sign or initial their work because in their world their style IS their signature. I can't propose a value because engraved guns don't interest me, though I am happy to acknowledge the skill and vision that went into making a thing that I don't want. That style looks familiar to me, meaning I have seen it on other revolvers, so it's probably somebody known. An engraved-gun aficionado should be able to tell you who it is.

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David Wilson