The Model 1891/59 Carbine is a modified Moisin-Nagant 91/30 rifle that is patterned after the M38 carbine.
Close-up of the 91/59 action.
Close-up the the modified rear sight, note that the higher settings on the sight were ground off.
Markings on the 91/59 carbine barrel shank.
The barrel, cleaning rod and forestock were shorthened to the M38 pattern.