Unit Markings on an Unfortunate "Hybrid"

[frankenlugerguy]

Thanks for the reply, Mark. Sorry to be late in getting back to you.
The serial no. is 3181N. The markings in the center of the grip strap are so faint that I can't really make them out. I'll try to get a good photo of them, and put it up; the "X" marks are visible, in the proper light. They're pretty faint, but I'll do my best with it.