Unissued v. Old

Okay, gun nuts. Tell me the facts.

There are some "unissued" Finnish M39 rifles on the market. They have "postwar" stocks on them. They seem cheaper than really nice used Finnish M39s. Using my finely honed cynicism, I deduce that there must be something wrong with them. My guess: someone in Finland took a bunch of metal gun parts that had never been put in stocks and crammed them into brand-new, possibly cruddy furniture.

Right or wrong? I mean, if "postwar" just means someone slapped a very nice stock on a gun in 1946, then these are great buys, right? But if it's something cut out of a discarded pine board, then it sucks.