George III, King of Great Britain and Ireland (until 1801) then the United Kingdom and Ireland (1738 - 1820) (Stamp 45)

Owner:
Arms:
Quarterly 1. England impaling Scotland; 2. France; 3. Ireland; 4. Tierced in pairle reversed: Two lions passant gardant (Brunswick); Semy of hearts a lion rampant (Lunenberg); A horse courant (Saxony)
Crown: sovereign
Order: Garter
Supporters: A lion gardant imperially crowned and a unicorn ducally gorged and chained, each holding a flag charged with the cross of St George (dexter) and of St Andrew (sinister)
Dimensions (height x width): 82mm x 88mm
Quarterings: 1. England impaling Scotland; 2. France; 3. Ireland; 4. Tierced in pairle reversed: Two lions passant gardant (Brunswick); Semy of hearts a lion rampant (Lunenberg); A horse courant (Saxony)

Sources