There was a NOS Legnano on e-Bay a while back that looked somewhat like yours, but it didn't have as nice a frame (Stamped dropouts, not forged). It had Campagnolo 980 derailleurs & universal brakes but the levers were Galli gg 80. PM me your e-mail & I can send you some pics that may give some help with original parts. Don
edit: Here's a few pics, many more available