Yep, its my opinion. Just like you posted yours.. which is frankly incorrect; and i am not sure what its based on. Perhaps in your area more pretty rifles are worth more.. i get that.. but in the grand scheme of things a nice war time sako unrefurbished is usually worth more than a refurbed m39 in a replacement stock.
The stock has its original finish, unsanded, unmolested. Which is growing increasingly difficult to find as the days go by; especially in a Sako war time stock. The rifle has a pleasant patina. Thats a 400-450 rifle all day long.
I know 9/10 here would not hesitate to pull the trigger on that rifle if it was posted on the trader, my self included.
On a another note.. I am still Not sure how a couple of dings in the stock is considered "beat up".