My grandfather James Kerwin was a piano and sax player in late 1930's swing bands. My mother brought over his vintage sax (that probably has not been played in 70+ Years. A quick google provided some info but I'd thought some experts might know a bit more:) thank you for your time!!!
Melody Master was a stencil made by Martin in Elkhart, IN. You can also tell it is Martin by the beveled tone holes and the way the serial number is stamped in the neck. Looks like the original finish (silver plate) to me, and since it is silver plating, it is just tarnished and would shine up like new and look great.