What so special about this "RARE German Kriegsmarine Steyr bnz"

[GeeRam]

The rifle is a Radom made rifle , not even Steyr . The stock stampings look fake , the M and W 623 is Steyr and should be W 77 for Radom .

They never assembled rifles at Radom, its a Steyr assembled rifle using a Radom supplied receiver, which was common for Steyr production, who used a lot of Radom supplied components (Radom never made barrels, hence never assembled complete K98k's)
All marking seem consistent with a known matching g block bnz 41.

Steyr had a large contract with the Navy in 1941, so not uncommon, but if its a true matching rifle, the price of it now at $5k is about right these days.
Stock markings do look 'crisp' but don't look 'fake wrong' if that makes sense....