This is a cover, posted from Harlow in 1993, with a Royal Mail stamp on the front (the 1992 Single European Market issue), and two “Lundy” labels in the style of a Penny Black and Twopenny Blue on the reverse. Each one bears the Lundy name, the initials “J” and “A”, and the value in puffins, and is cancelled with a red Lundy handstamp.
We are not sure of the origin of these labels, but it is evidently not a genuine Lundy issue. Nor is it believed to be the work of Gerald King, who has produced numerous fantasy issues for Lundy over the years, many based on historic stamp designs. Perhaps the mysterious “JA” is key!
Wherever it has come from, it’s certainly an interesting and unusual Cinderella item, and not something we have seen for sale online before.