very interesting frame: I do think you have something from the European market but there are some similarities to the approx. 1979 US model Grand Record. For example the long-point BCM lugs, the Huret ends and the cable choices which have above BB for the drive cables but clamp-on shifters plus cable barrels for the rear brake cable.
Also the fork crown appears similar.
If yours is built from the same spec'd tubing it may be 3-mains Vitus 172 and fork blades, the remainder unknown steel.
Never seen a BB shell with what seems like the FD guide snapped off or...?
otherwise good chance the components were different as the USA model came with mostly Shimano 600EX.
the seatpost is a bit suspect I suggest you check the OD of the seat tube to determine if this frame has Metric or Imperial tubing and then re-check what seat post should fit a Vitus 172 tube (assuming this is what you got).
Take a look at this catalog scan from Velobase and see yourself what I have been referencing: Motobecane Catalog 1979