1939-1954; based on the lack of details in describing the shotgun the value could be in the 100-1000 USD range.
The Marlin model 24 shotgun was produced by Marlin from 1908-1915.
Marlin made these for Sears but I do not know the exact date when they started or stopped producing them for them.
The Marlin model 26 shotgun was made from 1909-1915.
Year of manufacture for a Marlin 880 SQ, 1996
103.-- on a Sears Roebuck gun indicates manufacture by Marlin. I don't find a 103.7, but 103.72 and 103.74 are listed as Marlin Model 59. Brophy in his book, Marlin Firearms, a history of the guns and the Company that made them, published in 1989 by Stackpole Books, lists the Sears Ranger 103-7 as a 16 ga. Marlin Model 90 O/U shotgun.
Marlin doesn't manufacture handguns.
your marlin was produced in 1968.
Your Marlin model 21,which was the straight grip version of the model 19 shotgun,was made from 1906-1907 by the Marlin Firearm Company.
The Marlin model 24 shotgun was made during the years 1908-1915.
it is a 410 ga pump shotgun
Your Marlin rifle,not shotgun was made in the year 1972.
Marlin Fireamrs by Brophy.I can say that the Marlin model 55 shotgun was made from 1950-1965.The marlin model 55 goose gun which had a 36in barrel was made from 1962-1996.