I have this label from the Post Office, New York, N.Y. (N.Y. 3107) described as "International Parcel Post, Collect 15 cents", with "GPO 5-10701" as shown below.
Does anyone know when this was printed, and how it was used? Was this label applied for outgoing Parcel Post mail from New York, and 15c postage applied at New York?
Is there a reference book on this type of label? Any guidance on valuation?
Thanks in advance, Dave