Stevens 30-30 Vintage Bolt

My wife has her fathers rifle which is a Stevens without any serial number it is marked Stevens Model 325A and J STEVENS ARMS Co., Chicopee Falls, Mass USA Proof Tested 30-30 It looks a lot like the Savage Model 325 even the same barrel lock nut. The barrel is 20 inches and is fed by clip holding three rounds. Can anyone estimate date of manufacture? I have not de-stocked it but wonder if a serial number could be underneath?
Any information would be helpful to her.

Serial numbers on all makes/models are almost always visible - and must be visible on anything made after 1968. Prior to 1968 serial numbers weren't required by law and a lot of the cheaper utility models didn't have them.