That's an excellent quality psu, if not serious overkill for a single gpu. You can run upto sli gtx 760 or x-fire 280x with that psu.
For a gpu less than $250 you're looking at r9 280 or gtx 760, maybe a r9 280x if you get reall lucky and find like a 'black Friday' type supersale as those cards generally run $260+