Otto:
Yes, the repair/reproof mark will accompany the original marks, typically on the replaced component. I'm not sure if a weapon was fitted with a new tube that the tube would wear the new weapon proof stamps while the frame would have a repair/reproof stamp. Whatever the alteration, it must have occurred in early 1945. There is a obscure/little known and infrequently implemented rule for tipping weapons with rimless(?) cartridges. If, if the caliber or bore cannot be located in the proof tables, and I assume this to include cartridges, then the stamp for the calibre dimensions is waved. All the above is based on me having the rule correct. The proofmaster had quite the discretion in this article. This rule took the cartridge shackles off the gunsmith and allowed him to take odd foreign orders for cartridges not found in the German domestic market. Maybe the fella in Stuttgart that ordered the 1000 rounds of 7X75R Vom Hofe SE ordered this stalker also. I don't know who else might have ammo for the longarm if indeed the bulk of sporting arms cartridges dropped off in 1942. Or with a higher probability, Walter Gehmann recognized that Ernst August Vom Hofe was on his deathbed and snuck a few 7x75R Vom Hofe SE examples out before WWII ended it all for everyone. Walter Gehmann may have decided to mount a takeover earlier but the end of WWII put a kink in his plans.
Kind Regards,
Raimey
rse