What model????
Winchester made the Sears Model 200.
Depends on model and condition. Typically $100-$150.
$125-$175.
High Standard. http://www.histandard.info/PDF/Sears%20Shotguns.pdf
Sears Slug Model 446.511761 is a Mossberg 500. All parts interchange.
I believe that your Sears shotgun is a Winchester model 37A shotgun that was made for Sears Roebuck And Co,.
Winchester
about $100
numrich gun parst e-gunparts.com this is a complet book on parts and prices.
about $100
The value of a Sears Roebuck 12-gauge 101.100A shotgun is around $100. This depends on the the condition of the firearm.
The Sears Roebuck 12 gauge Model 583.606 was produced in the early 1970s. Specifically, it was manufactured between 1971 and 1973. This shotgun was made by the High Standard Manufacturing Company for Sears.