Our recycle center gets parts all the time. One guy that is local has a stack of parts. I was once going to buy an old french road frame/parts from him for 30$ Little did I know the frame was worth at least 100$ oh stupid me...It turns out our local recycle center will sell bike parts off pretty cheap. My uncle got a Motobecane frame for 2$. He says the color is blue. I am guessing he probably got a Nomad or Grand Touring frame. I only have the paint color to make wild guesses. I asked if the lugs were regular or fancy. He said fancy. Did motobecane make blue bikes with Nervex Lugs?
Moto made several models over the years in various shades of blue. Teal blue GTs and Le Champions come to mind. There was also the Team Champion in a totally boring blue, along with the more mundane models. A Le Champion might have Nervex, depending on the vintage.