Don´t believe that it is an Original Oberndorf in 6,5x55 . Action , sight parts and stock are certainly Type B (following serial number produced 1932)
The barrel shank is untypical long for an Oberndorf barrel.
A close up pic of the number on the barrel shank will reveal , that it has been rebarrelled to 6,5x55.
I would suggest it has formerly been a 8x60 or 9x57 , because the configuration of the rear sight base in that thicker diameter was most often used in that calibers.