The 30-30 model 54 jc Higgins usually sells for $ 100.00 less than The comparable Winchester. Is this a rifle you are looking to sell?
Maybe, what is it selling for now a days?
I believe that your Sears shotgun is a Winchester model 37A shotgun that was made for Sears Roebuck And Co,.
Winchester made the Sears Model 200.
The sears model 6c-22 was made Winchester/ same as Winchester model#490
The 282 is the Winchester model 521 made for sears
It's a Sears & Roebuck made by Winchester and modeled after the Winchester 73.
Winchester 1200
It's actually a Winchester model 70 made for Sears and Roebuck.
No serial number history is available for the guns produced by winchester for sears.As to the value it appears that the sears model 54 is selling for between 175-250 dollars depending on the overall condition of your rifle and a bore in good condition.
100-300 USD
Winchester
I am pretty sure Sears made the Sears Roebuck model number you are asking about. You should only have 2 questions here not 3. The Model 54 was made by Winchester. It is a post - 1964 copy of the Winchester Model 94. You can see the store brand cross reference information at Numrich gun parts website.
e-gunparts.com or Jack First in Rapid City SDAnsweron a Winchester model 1200