Hey again guys!
I took the gun apart and took some pictures of all the markings I could find. Here are some pics:
These are the markings on the underneath of the (forearm?) when I took the barrel off:
This is a marking off the underneath of the barrel:
This is a marking located on the thing (sorry for lack of terminology) attached to underneath of barrel. It reads "74":
Marking on underneath of removed barrel stock. Reads: 1460:
Initials carved into underneath of removed barrel stock. Reads CAS
Carve into stock. Appears to read "Ozzng"