I don't think it'd even take that much for AJ. 2 years @ 14, or one at 8 might get it done at this point.
I'd rather roll the dice on Saunders though, who at this point, has a much higher upside. Of course, getting there and staying there will be the tricky part.
edit: Dude put up 2.4 WAR in 78 games in 2014...That's why you hang onto him and hope he can hobble for a little while longer.