Green’s Dictionary of Slang

tup n.²

1. 1½ (old) pence.

1912		C. McKay ‘A Recruit on the Corpy’ Constab Ballads 50: Last night me gie ’m de last-last tup.
1933		(con. 1900s) C. McKay Banana Bottom 317: Tub [sic]: a penny ha’penny.
1942		L. Bennett ‘Jamaica Patoah’ in Jamaica Dialect Verses 1: An wen me dun me tell har sey / Is jus’ two-bit an’ tup.

2. a very small amount.

1912

cited in Cassidy & LePage Dict. Jam. Eng. (1980).

In phrases

tup-an-gill (n.) [gill n.³ (1)]

(W.I.) 2½ (old) pence.

1943

cited in Cassidy & LePage Dict. Jam. Eng. (1980).