You don't mean something trivial like: "Alfa Romeo 2000 “Sole” Bertone"
No, if that was it I would have given you it.
There is something missing completely from the name, and it is an essential part of it.
It's not 'Alfa' or 'Bertone' or numbers but part of the model's name.
I haven't found it on the Internet at all (picture came from a book) apart from that one site you got the 'Sole' name from (which is part of the full name).
Think what might fit with 'Sole' (Italian for 'sun')?