I went over mine again after RTL questioned the lack of any markings, this time with a high intensity flashlight and discovered a few heretofore undiscovered marks...
There is a "3M" just behind the trigger guard
There is an eagle and what looks like a small "A" in front of the magazine cutout
And a "B" where the lower band would be
No signs that I can see of any metal rubbing wear or any indication that there was ever a rifle installed in this stock
Sorry for the confusion