A few observations (and responses to the responses you have had above):
1. A Model 19 is always a nice gun. Congrats on running that one down.

2. Although that Model 19 most likely did not come from the Factory as an "engraved gun", I believe that the gun was shipped back to the Factory where "Laser Engraving" was done sometime in the mid to late 1980s. Here's a Factory Information Sheet on what they were doing at the Factory:
3. The Factory did produce laser engraved guns, mostly 586's and 686's (from my un-scientific observations and as noted on the back side of the above brochure). I have a 586 so "engraved" in my collection, but I don't have any photos of it, but here are some photos of a 586 like mine from a closed GunsInternational sale:
4. From the two photos that you shared, the gun looks to to me to have been reblued at some point, as the roll marks are not very crisp and a bit rounded on the edges. Also, somewhere in its history, the majority of the color case on the hammer and trigger were lost.
5. The grips are not original to the gun. As noted above, it would have shipped with wood checkered target grips.
With all of that said, I really like your 19-4 and I think it will bring you years and years of enjoyment.

Thank you for sharing it with the rest of us!