Most Campag rims are under that and are all pretty strong. Atek's are around 380g, Stheno's and Mirox 400g-ish.
Stheno's are particularly strong and rigid.
This should be helpful.. I have campag stheno and atek and also araya 395's and 400's to my bikes and they are indeed very light. in '92 & '93 all had the quirky concave braking surface too..