Green’s Dictionary of Slang

ewif yeneps n.

also evif yeneps
[backsl.; evif n. + yennep n.]

five pence.

1859
18601870188018901900191019201930
1935
[UK]Hotten Dict. of Modern Sl. etc. 126: EVIF-YENEPS, five pence. [Ibid.] 127: EWIF-YENEPS, fivepence.
[UK](con. 1840s–50s) H. Mayhew London Labour and London Poor I 23/1: Ewif-yenep ... Fivepence.
[UK]Sl. Dict.
[UK]R.T. Hopkins Life and Death at the Old Bailey 65: Costermongers invariably use the following terms in discussing money transactions [...] Ewif-yenep – Fivepence.