Green’s Dictionary of Slang

(UK Und.) a banker; thus swapperchop-brammums, a bank.

c.1850

Duncombe New and Improved Flash Dict. n.p.: Stackel-flim a cheque on a banker; I’ll give you a Stackel-fim upon my Swapperchop – I will give you a cheque upon my banker. [...] Swapperchop-brammums a banking-house.