Marlin High Standard made the Model 75 20 ga semi-auto shotgun for Sears http://www.histandard.info/PDF/Sears%20Shotguns.pdf
For all intents and purposes, yes it is. Nearly every part is interchangeable. The Sears guns do not hold the same value, though.
The Sears Ted Williams Model 300, semi-auto, shotguns were made by Winchester. The Sears 300 is the same as the Winchester Model 1400.
In Excellent condition $200-250 It is a High Standard model actualy.
High Stadanrd http://www.histandard.info/PDF/Sears%20Shotguns.pdf
High Standard made the Model 75 for Sears. http://www.histandard.info/PDF/Sears%20Shotguns.pdf
The sears model 6c-22 was made Winchester/ same as Winchester model#490
If your Browning auto-5 shotgun is a 12 gauge model then it was made by FN of Belguim for Browning in 1907.If you have a 16 gauge model,it was made in 1921.
Sears' JC Higgins Model 25 is the High Standard model A1041 .22 auto
I must first say that sears did not keep any production records of the shotguns they bought from various makers.your sears model 102.25 was made by Stevens.The model of your shotgun is Stevens model 520A. These john browning designed semi auto shotguns had the hump back design noted on browning shotguns.these Stevens model closely resemble the savage model 720 with the same john browning design,and these were made from 1930-1949.
Auto 5
From the best I can tell, the Western Auto 325BB model was made by Mossberg.