note the treble shift slider, and the bass strap adjuster..
those suggest a pre-war model to me
it is big and black, so 1938 through 1940 or when production
was stopped because of the War
the multitude of RhinestoEven another make of accordion could possibly been modifiednes were likely added much later
by someone who more or less refurbished/cleaned it up
i would not necessarily believe it is a paolo unless you can find
other corroborating specimens.. i personally have never seen a Black Pre-War
paolo, as the shift to Black was an American driven thing, so any 'response"
in kind with a similar model was more likely by the accordion companies
with strong representation in New York
that is all just my slightly educated guess of course