It is (or was) a Czech VZ-24, made for Persia (now Iran). The left side markings are Farsi and read: "Carbine [short rifle] Model 1312, Brno Arms Factory". The original number was 12831. I have no idea who put on the "89" or what it meant.
The VZ-24 is usually considered among the best of the 98 Mausers and has been the basis for many fine sporters as well as a collectors item in the original condition.