All Matching and How Do I Repair the Finish on the Stock

[GeeRam]

This is stamped inside the stock.

Yep, Bn is the code for the laminate supplier for the stock, Sauer (or rather Haenel) appears to have changed laminate supplier in late 43, as most of the stocks from late '42 up to Nov 43 are coded Na.
The 2 48 43, is 2 day of the 48th week of 1943, so 30th November 1943, which fits with a Jan/Feb built rifle.