I am looking for someone to help me with identifying this stamp. I know not much is left, but there is one very distinguishing feature that remains, the border. I have looked at countless images online and have not found anything close that has a border design with this profile (circled in red on the image). The border design is an octagon shape (ie clipped corners).
For context, the age is likely between 1910-1920's based upon the item to which it is affixed. I would find it hard to believe it would be anything other than United States in origin. Were there private shipping stamps for freight/packages at this time? I have looked at just about everything I could find as far as US stamps from this period to no avail. Is it possibly a tax stamp? State issue?
It is 1 1/8" x 7/8" in size approximately. Any and all help is appreciated, I have been trying to run this one down for over a year.