Dear Christian,

Thank you for contacting Mearto with your appraisal inquiry. My sincere apologies for the delay with the appraisal.

The presented object appears to be a Steyr model 300 hammerless SxS double barrel shotgun with a barrel for 12 and 16 gauges.
Comparable objects were recently offered and sold on the international auction market.
This piece is in good condition and no severe damage is visible in the images provided.
A fair market estimation would be between 400 to 800 USD.
This estimate is based on actual recent past recorded auction sales of comparable items. Retail "asking prices" can be higher and may vary.

With kind regards,
Gregory