My car came with dual Weber 40 IDF 42/43 4C carbs. Put on long before I got involved. The issue is that due to many backfires through the years and too many owners, the aux venturis have been melted down enough to be useless. A mechanic I am using tried to sleeve them but it did not work.
It looks like these are very old carbs and those parts are NLA.
I have dimensions if anyone has some to offer, need 2 like the longer ones in the pic.