I'm not aware of Universal having made levers for flat bars that incorporated a barrel adjuster. The only Universal levers that I'm familair with are for racing bars.
You have a Chemineau! Is it one of the models with the proprietary derailleurs? That was one of the original, practical derailleur designs and extemely long lived. PLEASE post a picture of it!!!!
BTW, I can probably help you date your Univega, as most were built by Miyata and Iid so, I can decode the serial number.