Please try not to reference
http://7.62x54r.net/ as it is quite out of date.
For stocks with pressed escutcheons:
Izhevsk sniper stocks made 1944+ but they will have no cutout
Mednogorsk stocks but they will have a small circular cutout
Post-war with angular cutouts as in the OPs rifle
Yes, some stocks did receive some cutouts post-war. However, Mednogorsk stocks already had cutouts and Izhevsk stocks were sniper stocks only so unless you see a very obviously repair where the stock was cut for the mount...
Furthermore, post-war stocks will have some marking like a box with a like on the right side butt stock. Izhevsk sniper stocks will have the inspector's cartouche and CCCP roundel. Mednogorsk stocks will have a different inspection cartouche and the Tula Star. These markings can be almost completely sanded away.
I always find it funny when people are arguing things they don't know about :/