1977 Summer Isles set, featuring decimal conversion overprints on the previously produced definitives showing different fish alongside a map of the islands.
The earlier 1d, 2d, 4d, 6d, 1s and 2s6d denominations are cancelled out with a black circle, and replaced by 2p, 3p, 5p, 10p, 15p and 25p values respectively.
U/M / Unmounted Mint / MNH / Mint Never Hinged.
(Note: A similar overprinted issue – NOT this one! – exists from 1970, featuring lower-value overprints and with the old values cancelled out using black bars instead of circles.)
About the Summer Isles
Unlike a lot of the labels that purport to come from islands off the coast of Britain, Summer Isles stamps have always performed a genuine local postal function.
On 1 September 1970, due to the lack of an official postal service to and from the largest and only inhabited island, Tanera Mòr, the Summer Isles Estate was permitted to launch a private, year-round mail service to and from the mainland at Achiltibuie.
Attractive stamps were issued until 1986, before the service fell dormant until its relaunch under new ownership in 1996. The first new issue in three years was produced in 2016.
Today, the island hosts several holiday lets and the cafe and post office. Mail posted on the island must bear both a Summer Isles stamp (for transportation to the mainland) and a Royal Mail stamp (for its onward journey). After several years on the market, the island of Tanera Mòr was purchased by businessman Ian Wace in 2017, and is (as of 2019) undergoing a programme of restoration before reopening to the public.
The Summer Isles website includes more details about the Post Office.