Hello mate, welcome on VR!
The carburettor you're after is not exactly the most easy thing to find but it's not too rare.
To start with I found this, through a google search. Try that to start with, you may find some internet shop that stocks it, or you can search on ebay, at least on the italian, english and german websites. I am sure it will not be impossible to find, all you need is patience e perseverance.
