Hi, I would very much appreciate any help in identifying the MANUFACTURER, AGE, RARITY of this pocket watch. The movement and case have the same serial number, "34991". The cuvette cover is marked, "WINDING WITHOUT KEY"; the winding keys are fold-down. The case has 2 hallmarks inside the rear cover; "ARGENT (with a Chevron patter) and "FM (O or C?)" over "N" inside a box outline. The outer covers have detailed engravings of a train and sailing ships. The enameled dial has a cutout to the lower half of the subsidiary seconds register, with a lower 'rotating' enamel disc with a train engine and passenger car motif.