you need to see if you're crank is good, if so you might be able to get away with just a top end. especially if the hour meter is right. imo there is still 150+ hours on that crank if all the bearings are still good. never know what you're going to get with a used motor. even if you by it from a shop.
case in point: i sold my 787 out of personal xp to guy for a gtx. now i was never really genital on that motor and told the guy that, but i did take care of it. anyway after i installed it and cranked it up it ran as it was supposed to for 5 mins on the hose, rev'ed good and everything. right before i was about to shut it off, there was a horrible screeching noise. it was the rotary valve gear stripping. so i head to pull the motor back out, clean the shavings out and put a new gear in. morel of the story is for 500-800 bucks a used motor is just that: used.