This particular example, from the site author’s personal collection, is identical in every respect to a slightly older pair of Millers Falls 74Cs (seen here) with the exception of the glued-on paper label.
The model number prefix “107” is part of a standard Sears numbering convention indicating that the tool was manufactured by the Millers Falls Company. The “36500” is apparently just the model number assigned to the product by Sears.
As with their Millers Falls badged counterparts of the same era, the castings appear to be hand stamped with what we surmise to be a foundry identifier and a manufacturing date. The location of the stamp in this example is found on the underside of the casting, beneath the quadrant. In other models of miter box the underside of the swing arm bears these stampings. This particular specimen would appear then to have been made in 1969.
Bibliography:
Sears Craftsman Hand Tools catalog, 1964 (p. 35)
A Langdon Mitre Box Reference 