NORFOLK ISLAND. 1961 Definitive SG36s (10s) Overprinted "SPECIMEN" Mint, never hinged. NORFOLK ISLAND - 1961 10/- green SPECIMEN's. Two different overprint fonts. SG 36s. 1961 10/- green 'Tropic Bird' adhesive in unmounted mint condition handstamped SPECIMEN with another example but with a completely different font type. SG36s. (Image 1) (Image)