Savage Arms acquired Stevens Arms & Tool ca. 1922, and has since branded many of the "Savage" firearms, and the former "Stevens" firearms with various names, for different purposes.
Later, Savage moved from NY to Westfield, Mass, and the Stevens operations from Chicopee Falls to Westfield as well.
The "Riverside" & "Springfield" brands are the same gun as the Stevens 311 type, meant for the discount trade, while "Sears", "J.C.Higgins", "Ted Williams", "Revelation", Western Field", Western Auto", and many others were so branded under contract for those various outlet/chain stores.
Other major gun companies, like Mossberg, Marlin, Remington, & Winchester did much the same thing.
With those "store brand" guns, the barrels, actions, etc are the same as the top-of-the-line items, but are not as finely finished and usually have non-walnut, uncheckered stocks (but not all).
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