Thanks, Charlie. I wonder about the P on the grip, too. Doesn't seem like that would be there unless there would be a rebuild mark somewhere else. The same seller has another stock on eBay right now with the same size IO mark in the well, but also has an O in the barrel channel. I don't believe the K stock had the M2 cut but this next one does. The CC on this one (not a surprise) looks identical to the one on the K stock. - Bob