scale, n.¹ — Green’s Dictionary of Slang

scale n.¹

also shadscale

[SE scale, a thin piece of metal, used in scale-armour]

(US) money.

1872		Schele De Vere Americanisms 296: Among the less generally known terms [for money] are [...] wherewith, shadscales, or scales, ‘for short’.
1900		Flynt & Walton Powers That Prey 88: You let lots o’ chances to make scale go by.
1963		M. Braly Shake Him Till He Rattles (1964) 114: We can give you scale, anyway. OK?