Green’s Dictionary of Slang

(US black) three dimes, 30 cents; thus trey of sous and a double ruff, four nickels, 40 cents.

1944

D. Burley Orig. Hbk of Harlem Jive 65: The best thing for me to do is lay a trey of sous and a double ruff on the head hen and knock some joy for myself. [Ibid.] 149: Trey of sous — nickels.