Here is an example of a non-refurbished stock. Notice the way the date and serial number are stamped under the Tula cartouche. Also notice the original Tula inspector stamp on the opposite side of the buttstock, as well as all of the small inpector marks around the cross bolt.
Your stock was sanded (you can still make out part of the original serial number with cryllic prefix) and re-finished during the arsenal refurb and then re-stmaped with the 4 digit serial number.
---------- Post added at 09:26 AM ---------- Previous post was at 09:20 AM ----------
I wouldn't have cleaned it but I don't think it will hurt the value, especially since it's a refurbished rifle.