Yeah, the magazine is clearly a modified 10 rounder. The font doesn't seem to be out of place, I'd have a hard time thinking bubba stamped it, but it's impossible to say for certain. Looks more likely that he took the original mag and cut it down. In the side view, you can see some uneven cuts that were made at the top of the mag and the tab on the mag where the mag catch latches onto is pretty rough. I think bubba modded this one and it's not one of the nicely done 5 rounders from China.
The front sight hood is cut off just like a Poly Tech Hunter, I had missed that before. That is a very uncommon mod commercially. Everything is leaning towards Bubba. It's definitely an oddball gun, I wish XXX was still around, he would probably know at least where to start on this one, I think Bubba got ahold of this one though.