Single shot break action shotgun? If so, most likely a Springfield 947. Depending on condition, value is about $75. Well made, reliable shotgun- just not a very pricey one.
Springfield
sears roebuck and company
The value of a Sears and Roebuck 12 gauge shotgun model number 281512651 depends on its condition. This gun in excellent condition is valued between 100.00 and 135.00 as of 2014.
Winchester 1200
1952 by High Standard for sears& Roebuck
$49.95
http://www.histandard.info/PDF/Sears%20Shotguns.pdf
I believe that your Sears shotgun is a Winchester model 37A shotgun that was made for Sears Roebuck And Co,.
75-200 USD depending on condition.
We have them. gunshop@nctv.com
I have parts for that model. sales@countrygunsmith.net
The value of a 12 gauge Sears and Roebuck single shot bolt action model 14 will vary depending on the condition. If the gun is in good condition, it could be worth $150-$200 dollars.