The 1640/1600 are less prone to crack at the tang than the 640. to prevent the crack, HVA used a either a SS (only on certain models) or a brass threaded rod through the web between the magazine and the trigger well. If the stock was bedded, the reason behind the operation often was a cracked web, so there will be no need to do any more intervention.
The value of an all original 4000/4100 may be between 400.00 $ to 550.00 $, depending on caliber (the 7X57 may bring higher prices) and condition. As a collector standpoint, a bedded stock will often lower the price, depending on job finish.
The 30-06 is the most common "lightweight" chambering, but at the end, the value is how bad you want the rifle.