Thank you for the replies.
Gil - i did clean the hole/slot out. The bayo did not come with the rifle but is a 1909 manufacture like the rifle. Also US marked.
Jim - the back of the bayo has been hammered significantly. Did not notice this before. Why would someone do that? I think the damage is just to the back. I am not sure what exactly is the side of the cross piece. Here are a few more photos.