Brad,
I think there was a "Marine Blue" from at least 1957-1958 and it was a dark blue, similar to the earlier Mariner Blues (the two hues of Mariner Blue between 47-55) and the 1956 Regal Blue. In 1959, it looks like the dark blue (Harbor Blue) was metallic.
Brother's seems to a little off in the names and in the shades of blue.
Are you looking for a touch-up can (of 1950 Mariner Blue)? I got a touch up "pen" (1954 Mariner Blue) from a company that also packages cans to any color code (I think they are in CT). Brother's is a lacquer but I think the CT company packaged acrylic enamel.
Tim
