The camo stock could very well be aftermarket, that is a camo pattern normally seen on shotguns used for waterfowl hunting, not on a rifle. #2 does not appear to be a factory stock either. The metal pin through the middle of the stock means it was made for something that kicked a lot, possibly one of the big bore magnum African hunting rifles. They most likely fit one of the variations of the model 70, but more photo's from different angles are needed. There are at least 4 different generations of stocks with slight differences. You have Pre-64 rifles, and then the push feed rifles made 1964-2006. The model 70 Classics made 1992-2006, and the current production rifles use yet another stock. They are similar and it is sometimes possible to modify one to fit a different generation, sometimes just using different bottom metal is all that is needed.
#1 appears to be an older stock, possibly pre-64. It has a lot of drop and was designed to be used with iron sights. #3 looks like one of the Classic Sporters and it appears that the sling studs are SS, they did make some SS rifles in walnut stocks. #4 isn't walnut. It came off one of the cheaper budget guns, possibly a 670 or one of the Rangers. I'd guess it was a 1970's era stock.