When was a single shot 12 gauge by Delphian Arms made and what would be the value of it?

With only the name to go on, the stock answer is "about 1900" but it could have been made as late as the 1940's. Value will be $35 - $75 if it is a shooter with fluid steel barrels or about the same amount as a wall decoration if it has a large side hammer and damascus barrels.