Seychelles. (Zanzibar - Postage Due). 1957. Envelope addressed to Zanzibar bearing Seychelles SG 191, 5c on 45c purple-brown (pair) tied by Victoria/ Seychelles date stamp 'Sp 23 57', underpaid with m/s '8c' in blue crayon and bearing Zanzibar postage due SG D25a, 5c violet tied by blue pencil cross.
Very rare item of postage due mail into the small island of Zanzibar.