Joachim, I asked Luca, and he signed me up to the Gilera4T forum.
After a bit of a struggle (the nearest I know to Italian is basic Latin from 65-70 years ago), I finally got to the "Vendo" section. If you search there, you will eventually get some idea of what he has. it would take me all day to flog through and list individual Nordwest stuff, but the "Y" manifolds are there clearly visible at Euro 55.
However, I see you are already a member there, so if your italian is better than mine, perhaps you could make a list of his stuff?
Les.