What would be the age and value of a riverside arms 12 gauge single shot break over shot gun with a sn 403e?

Determining the age and value of a Riverside Arms 12 gauge single shot break action shotgun with serial number 403E can depend on several factors, including its condition, any unique features, and the local market. Riverside Arms produced shotguns primarily from the late 1800s to the mid-20th century, so this shotgun could be anywhere from 70 to over 100 years old. Generally, such shotguns may range in value from $100 to $300, but prices can vary widely based on demand and condition. For an accurate appraisal, consulting a firearms expert or appraiser is recommended.