The Standard Catalog of Firearms lists 67 different side by side models made by Stevens. Many of them had exposed hammers, either back-hammer boxlocks or sidelocks, and most were manufactured during the time "A&T" was included in the name (1886-1916). If your gun has twist or damascus barrels, it is basically a wallhanger. If it also has side hammers, then at least it is a wallhanger with some value - generally $125-$150. If it has fluid steel barrels, regardless of the hammers, it could still be a useable gun if approved by a qualified gunsmith. Value as a shooter would be $200-$250.
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I can't find production dates for a model 357, but if it is marked J Stevens Arms Co (NOT J. Stevens and Co or J. Stevens Arms & Tool Co), the gun was made no earlier than 1920 and before 1950.
1930s
The model number should be on the right side.
1864-1926
Probably $50-$75.
Made between 1890-1920.
Both 'King Nitro' and 'Central Arms Co' are trademarks of the Shapleigh Hardware Co, which was a major catalog retailer from the late 1800's well into the 20th century. The shotguns marketed under that name were made for Shapleigh by different companies, notably Davenport Firearms, Crescent, Hopkins & Allen, and Stevens. We'd have to see the shotgun to determine which manufacturer actually made the shotgun. www.countrygunsmith.net
I can't find this model number, but that form of the company name was used from 1920 until 1948, and a 410 double will bring $200-$300, depending on conditon.
Riverside Arms is a brand name used by the J Stevens Arms Co. on many good quality shotguns. The value depends on model, gauge, and condition. There is little collector interest in single barrel shotguns. Information about J Stevens Arms apply to Riverside Arms Co.
If your gun says " J. Stevens Arms and Tool Co. " it is pre-1920 and post 1910 or maybe a few years earlier. Information to that degree of detail is hard to come by. If it says " J. Stevens Arms Co. " it is post 1920, after Savage purchased the factory. It is a very hearty, stout and reliable shotgun. It is a utility grade shotgun that is very well made. I am refinishing the furniture and exterior steel on mine. The action needed no attention but cleaning. Not bad for a 100 Year Old Shotgun.
Impossible to answer without more information.The manufacture date can be approximated by the company name.J Stevens & Co = 1864-1886J Stevens Arms & Tool Co = 1886-1916J Stevens Arms Co = 1920-late 1940sStevens = 1940s-1990