Green’s Dictionary of Slang

(Irish) money.

1981		(con. 1920s) P. Crosbie Your Dinner’s Poured Out! 220: goyno money.
1982		(con. 1930s–50s) E. Mac Thomáis Janey Mack, Me Shirt is Black 30: On St. Patrick’s Day we could eat sweets and if we had the Guino (money) we could have the pics.