DUDE!!! that is no contest, the 721 is one of the most accurate factory rifles ever built. I think it, fireing a 222 cartridge, held the benchrest record for something like over 50 years. If it also has both complete front and rear site sets, those alone are outstanding. Step/block rear site , totally adjustable, with the massive sharkfin front site, fully ramped and lined, with double screw in set screws. If it looks as good as that one in the pic, around here, you couldn't touch that for less than 500 bucks.
Now then it could have some probs, so you should get a 3 day return guarantee on it, and go fire it. First make sure the safety works; try to fire it
with it on. Then you should work the trigger several times, make sure it doesn't start to feel like mush-- if they were ill taken care of, they can be nasty if left alone. Fortunately, Timney makes a drop in trigger for this, that is excellent.