The best I can see it is a three-digit number 179. Certainly not a Remington era repair code. I have an 1889 vintage, heavy, Damascus barrel, 2-frame, 12-gauge, GH-Grade that was fitted with a second set of Vulcan Steel barrels in 3-inch 20-gauge, probably some time in the 1918 to 1926 time frame. My barrels have a 153 in that location on the left barrel flat.
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