(read how to identify your stamp below)
You have the 7¢ Stanton from the years 1871-1875. It is fairly uncommon.
If the stamp has a grill embossed into the stamp, then click here.
If it does not have a grill and does not have the secret mark (as shown below) then click here.
If it does not have a grill and does have the secret mark (a semi-circle as shown below) then click here.
Without semi-circle secret mark
This stamp was reprinted in 1875 and it can be viewed by clicking here. These are all accounted for, and be accompanied by a certificate.