No missing link here.
It's a 7th year carbine (1962). Looks like one from the Albanian caches-- the import stamp will confirm or deny this. With a 7mil serial it's likely an I.O. import.
The missing serial number on the stock suggests that it has possibly been refinished or (imho, more likely) it's an Albanian-made replacement stock-- a fairly common trait on the Albanian imports.
How many holes in the butt-stock plate?