Seems how this is still floting around will update. i cleaned em up and the top part comes off so you can take the glass out. theres 2 round pieces one with and artch to both sides and the other only one side is artched the other is flat. Heres a pic of the glass.
Mouse, I had a 22 cal. squirrel gun (rifle) that had a scope exactly like that (the center is missing) but each end looked just like your artifacts. HH omnicognic 8)