SAVAGE most likely. They produced a number of these for SEARS including the model 101.40B. Would be nice to see a table that shows the identical SAVAGE model no's, so I can order parts for one myself too...
I believe that your Sears shotgun is a Winchester model 37A shotgun that was made for Sears Roebuck And Co,.
need a diagram of sears model 66m shotgun for takedown
You will need to find out who made it first.
1949
J. Stevens for Sears Roebuck.
The Sears Roebuck Model 300 12-gauge shotgun with serial number 273521160 was manufactured in 1964. This shotgun was produced by the High Standard Manufacturing Company for Sears, Roebuck and Co. It is part of a series of firearms sold under the Sears brand during that era.
Stevens Arms made the Ranger shotgun for Sears & Roebuck. Production ended about 1930.
Stevens model 18D
Probably Harrington & Richardson
Winchester
mossberg 500
High Standard