The way that insert is finished...or rather relatively not finished is kind of a tell. I don't know any "good" makers that have an insert looking like that. With that slightly conical shape it might be compression fitting. Usually I think you want a wood compression, not the brass insert itself though. Did you screw it together?
That does look like it might be an Ivory ferrule.
Interesting weight bolt looks like it was machined down after installation? No hex or slot for purchase in the case of tightening or removal.
Pawn shop background? No further pics? I am assuming you didn't grab it?
The Delrin butt cap and joint ring style evoke several good makers but nothing specific comes together with the rest of it, at least for me.
Maybe someone else knows.
Side note, whoever zip tied it needs a good smack on the head.
