Whatever the source, I cannot find any specific designation for this project. The only name I find is "ВАЗ-2108 Тарга" (VAZ-2108 Targa) though on a single picture of the prototype the plate sports the name "ВАЗ-2108 КЦПЕ" (VAZ-2108 Coupé).
Or maybe I misunderstood... I realize that I just called it "Lada Samara" which is obviously the export name of the production model, rather than use its original name "VAZ-2108"?