Green’s Dictionary of Slang

a shilling (five pence).

1861		(con. 1840s–50s) H. Mayhew London Labour and London Poor III 206/2: We could average our duey bionk peroon a darkey, or two shillings each, in the night.
1891		G.R. Sims ‘Pickpocket Poems’, Dagonet Ditties 91: Of two bioncs I robbed the bard, / For which I got three months with hard.
2010		W. Ings ‘Trolling the Beat to Working the Soob’ in Int’l Jrnl Lexicog. 23:1 64: [A] shilling was a beyonek, a half crown, a tosheroon, and a pound a ponte.
2023		R. Milward Man-Eating Typewriter 147: [T]hese twats might [...] take off with my hard-earned beyongs.