Did Stevens add a star in front of the serial # when a gun was sent back to the factory for modifications? I just bought a Stevens Model 40 Pocket Rifle so marked that has had the grip lengthened and longer grip panels added.  The metal extension is Nickel plated brass in 3 pieces soldered together and looks almost too good to have not been factory. The seller thought the star in front of the serial # indicated that it had been back to the factory. Anybody familiar with this?