"W-B" -- A Winchester Stock on an IBM?

[painter777]

F4Rio,
1st thing: The Hand guard wasn't made by WRA. But it is a nice match to your stock.

Your stock is a WRA Type III, a very nice one at that. Your picture #12 shows the position of the barrel band spring. This L shaped spring, where it goes in to the rear of the front barrel channel shows us it's a short channel.
A long channel would have more wood channel to the rear of where the spring enters the stock.
The CC stamp looks legit to me.
The stock nose shows use of a early Type I/A barrel band, more than likely the indentations forward of this area are from the band resting while apart. Though still a slight chance it may have had light use of a wider Type II or III band.

As already stated if this stock/assembly was accepted by IBM it would have the smaller IBM sized CC on it.
IMHO: Someone has added The W-B. Many of these original WRA stocks didn't have a small W stamped in the sling well. Many were stamped so light you'd barely find them. Put years of wood swelling and drying and it makes it easy for that tiny w to go bye bye.
Just the sliding back and forth of a sling over years of use would wear the area down.

If it were mine??
I'd try a bunch of tiny pin pricks in to the letters W-B and try steaming them up , maybe trying the tip of a solder iron or one of the fancy new household steam cleaners that you can direct the steam at.
Nothing to lose..... but 'Bubba' added letters.
It is a valuable stock.

HTH,
Charlie-Painter777

P.S. Here's a link to tips on WRA stocks, you can see/feel for comparison:
WRA Carbine Stock Traits