vibration in a ski nautique 2001

I am looking at a 82 sn 2001, the guy said he hit a stump and put a small ding in the prop and it has a small vibration. Could this be caused by the prop being out of balance or could the shaft be bent?? I just sold my i/o and would like to get a sn2001 until i can afford to buy a newer boat. He said the vibration is not bad...but bad to him and to me could be different. What could i possibly be looking at?