Remove the butt plate by removing two screws. Look down hole in stock and see stock bolt head. Choose correct flat blade screwdriver to match the slot. Be careful to not break through thin wall of wood when removing stock bolt. When bolt is loosened, slide stock back off of receiver.
It a Savage model 30H
Try e-gunparts.com
Your rifle was made by Savage for Western Auto. It is a Savage Model 46. You can contact Savage for an owners manual. It is a very basic bolt action. Remove the screw on the underside of the forearm to take action out of stock. Push the 2 pins out that hold the trigger group in place, and you can remove the bolt. gunpartscorp was a schematic at their website, under savage 46.
Try on www.GunBroker.com They list stocks for the Savage Model 99. I have bought several from this sight for my Model 99 Collection.
Try searching for a Savage model 620A or Stevens 620 stock on ebay, or gunbroker.com. The model M060 Westernfield is a Stevens 620, while a Westernfield model 60 is the Savage 620A
custom proposition
400 dollar range
www.boydsgunstocks.com/Replacement-Stocks-Stevens
A breakdown of the parts for a Stevens Savage Arms Model 9478 is found in the book The Gun Digest Book of Firearms Assembly/Disassembly Part V - Shotgun. It has exploded views of the stock and its availability on the market.
The 318 generaly gets any were from 225 to 235. That is if it is bone stock.
Answering "What is the value of a 22 caliber Savage Model 6A semi-automatic rifle with walnut stock and scope?"
remove the buttplate screws, and the buttplate. In the large round hole in the stock is the stock bolt. That is unscrewed to remove the stock from the rifle.