Green’s Dictionary of Slang

medzers n.

also measures
[abbr. madza caroon under madza n.; measures is mispron.]

(Ling. Fr./Polari) money.

[UK]R. Hauser Homosexual Society Appendix 3, 167: Measures, money.
[US]B. Rodgers Queens’ Vernacular 137: Money in general: [...] measures (Brit gay sl, fr Parlyaree medzer = halfpenny // It mezzo = a half).