Can't give an exact date, but Stevens used the Riverside name from about 1920 to 1945.
$60 to $100
Sorry- that is a serial number, and conveys no information. If the barrel is not marked, you need to take it to a gunsmith who will measure the chamber- not only for gauge, but for the correct shell length. Just because an unfired shell fits does not mean it is the correct shell. And it is not a rifle, but a shotgun.
On the breach under the barel
Under trigger
What year was riverside, 12 gauge, single shot ,model 548 made
Might have been a serial number, might be an assembly number. sales@countrygunsmith.net
Riverside Arms was a tradename used by Stevens and later by Savage. Would help to know what other markings are on the gun.
riverside arms co. split single shot gun
What is my 12 gauge dated oct 20 1915 from riverside arms in Chicopee mass. Worth. Number 48780.
NO!!! A 12 gauge shotgun takes only 12 gauge shells. A 20 gauge shell would fall into the barrel and get stuck about half way to the muzzle. You would be in for a nasty surprise when you put a 12 gauge shell behind it and pulled the trigger!!!
On the bottom of the receiver forward the trigger
On the bottom of the receiver forward of the carrier port and trigger