I think it would use whatever manual they were using at the time for the Model 19. I do not believe they change manuals each time there is an engineering change. The 19-4 was introduced in the late 70s, so I suspect the folding instruction sheet and two-piece cardboard box with the metal reinforced edges would be correct. Often, they used a gray box for nickel guns, but also I think if they were out, they used what they had. In addition, I am not sure when, but at some point, they stopped using the gray box and used all blue boxes. Your gun, however, pre-dates the one piece folding box with the insert.