Tool ID needed

not sure what it is or does, lever lifts and looks like it cuts something on the downswing, 90 deg angle turns and runs in the slot. anyone have an idea? thanks

 

H.B. Rouse Letterpress Typesetter Paper Press Hand Miterer | Etsy This looks like it

 

perfect. one of my older car friends came down and said he worked in a print shop during college and this looked like something to cut lead. then we both agreed it couldn't be. thank you.