I have found a stamp attached to a piece of an envelope but unfranked. The stamp is a 1966 world cup stamp showing cost of stamp as 1/3 (exactly as on stamp) of course this means one shilling and three pence. Depicts two players and a goalkeeper in goalmouth action. Stamp looks unused and in perfect condition and is placed next to a one penny blue coloured stamp showing head of Q.E.2. I would love to know the value of this stamp?