When you mail your letter don't use the 'make-up' series stamps. Stamps on mail to another country must show a money value. Don't put the Italian postal code at the end of the address. I am told that US postal employees might confuse it with the ZIP code. Italia Be prepared to wait.
Most people experience long delays in receiving a reply from Italy.
I jokingly call this my 'death threat' letter, although the tone is hardly threatening. The public law referred to requires that an official respond to a request for information within 30 days of the request. This letter is powerful. I have always gotten a prompt reply. Dopo tre mesi non ho ancora ricevuto alcuna risposta.