The value of your Parker and Greener, are based on the model, grade and condition of each piece. With that said, you should visit a reputable gun shop in your area and have them appraise your guns. Let them know that you are interested in an appraisal for insurance purposes and not what they would be willing to buy them for. Good luck.
1829 to 1869
I have a circa 1874 W.W. Greener double barrel shotgun. It was made in Birmingham England. It has double hammers with nice engraving. Greener shotguns are still produced today but in limited numbers.
Greener is one. There are dozens of others.
I have two 1878 Jas Parker & Sons double barrel shotguns.
Many makers made double barrel 8 bores british ,p.webley ,greener,are just a couple. then there wher American ,Parker, and i believe armi in the sixties made some
To answer your question quickly,the answer is none.Parker Bros.began production of there shotguns in the year 1866.They continued production until 1934 when Remington took over production and then moved the plant to Ilion,New York in 1938.While you mave have a shotgun dated to 1840,this would not be a Parker Brothers shotgun.
Parker double barrel serial #131072 what would the grade be and date made.I can say that with the serial number provided,your Parker shotgun was made in the year 1904.As to the grade,that would be impossible to say without a detailed description of the shotgun in question.you may find that there is much info available to you thru the internet about parker shotguns that will assist you in deciding which grade of Parker shotgun you have.
CHeck the frame, receiver and barrel.
Many of the shotguns are valued in price close to $5,000 each. The amount will vary depending upon the condition that the shotgun is in.