Unusual spot for a rebuild stamp?

Several weeks ago I picked up a "well used" PJ Type 3 replacement stock. I was pretty sure I had everthing about it figured out at the time of purchase - then a couple days ago I was putting some oil on it, and noticed what I thought was an unusual stamp on the bottom of the pistol grip. It's got the letters BA-BD in a small rectangle. I recognized it as a Benicia stamp and then did some checking on the net. I saw a couple pictures of similar stamps - several on 1903's and at least one on a carbine, but it was on the left side of the butt stock, and much larger. I was't able to find it in WarBaby, either. Question is: At some point was it authorized to have the stamps on the bottom of the grip, rather than on the butt stock? This is a pretty small stamp, and not sure there would have been enough room for a "P" there if it had been necessary. Also, can anyone identify the name of the inspector? I'm guessing the time period would have been late 40's or early 50's Thanks! - Bob

Unusual, yes. Unknown, no. There were a couple of other rebuilders who did the same thing, but I don't think they used the arsenal mark. I think Springfield was one of them.