I don't have one in front of me, but if it's like other Model 94s you should be able to just grip the forearm near it's muzzle end and pull it off. It's probably held on by a spring like other 94s.
The Model 620 was produced from 1926-1945. sales@countrygunsmith.net
1926-1945
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
http://www.gun-parts.com/index.html/
stevens model 620
Check the receiver and barrel.
what is the value
It's a Stevens 620.
I am presently looking at buying a model 620 pump and have found the manufacture dates to be approximately 1927 to 1954. Good solid guns. At least the one I am looking at is. All machined parts, no stampings at all.
model 620-a
what year was model 620- serial# 11240 made
2 3/4