A scarce cover signed by Doris Gray. The Postmistress of Haroldswick Post Office. A special Royal Mail Commemorative Stamp was produced in 1977 for Haroldswick P.O. the most northerly post office in Britain, specially postmarked by the Royal Mail at Unst. Shetland Island. Only 200 of this scarce cover were postmarked and signed by the Postmistress nearly two decades ago. Rarely offered for sale.