I bought the gun today at a gunshow from a guy I've dealt with before. The gun looked right as rain so I bought it. It wasn't until I got it home that it occurred to me the bolt root wasn't stamped with the letter suffix. The gun is serial number 6657a. Then my attention was drawn to what looks like welding pits around the bolt serial number. Looking at it with a jeweler's loupe it looks like the original serial number was ground off, filled with weld then restamped. That caused me to look at the shroud and it looks like the same work was done to it.
The bolt looks right and it is marked with the intertwined WR.
The bolt looks right and it is marked with the intertwined WR.