The hrs are not bad for a commercial mower. Most guys get 1000 (often a lot more) hrs on the Kaw. motors. They are nothing like a residential Briggs.
Check the hydros - make sure they pull evenly and are strong without a lot of whine. Check the spindles on the mower and make sure they are tight. Make sure all the grease nipples have been greased (good indicator that proper maintenance was preformed). Tires should be fine with those hrs. Also check the deck for bends/cracks/etc
Good luck