For such a small area, a couple hours one afternoon should get that cleaned up real slick, just pick them up.
I spent much of my youth spring days picking rocks off this farm, 8.7 million square feet. Wife & I now drive around a couple days with the Polaris and get 10-12 loads with it each spring.
Not a big deal.
As mentioned, they won't ever 'end', you won't finish. For a grass crop, you just want the surface cleaned up, a roller hwlps to push the missed/ late ones go back down to the surface so that aren't trouble. The landscape rake will help pull some to a pile; but it will also dig more of them up. Sorta 2 steps forward, one step back....
--->Paul