If you look at picture 2, the nub/stop for the clamp on shifters is bulky. Go down the downtube and you'll see what appears to be a FD cable guide in front of the clamp on cable guide. On the DS chainstay, is a RD cable guide. The bulky clamp on shifter stop could be cable guides, or not. I'm thinking the bike may have came originally with stem shifters.

The build reminds me of my lower level Lejuene. I replaced the cottered crank/BB with a Stronglight and upgraded the rest of the components.