its a real mish mash of components...The brakes are Shimano 600 'arabesque' from the mid 80's, the Shimano Crane rear derailleur is earlier than that by at least 5 years. The front Derailleur is probably one of the newer parts on there.

interesting Fork Crown




I was trying to look and see if I can see Forged or stamped dropouts, but instead noticed that the rear derailleur cable stop on the chainstay is mounted upsidedown. Flipping that over the right way should improve the shifting.