Well, could be draglink ends, tierod ends, ragjoint, or the box, yeah.
My experience is that the boxes lose power assist more than get sloppy, but ymmwv.
Oh and check the u-bolts on the axle for tightness!
As for slop, watch for where the movement stops when somebody turns the wheel ... does the rag joint turn on top of the box, but not the shaft it connects to? (Repalce rag joint.) Does the box move, but not the steering arm? (Box.) Does the draglink move, but not the arm? (Draglink ends) Does one wheel move, but not the other? (Tierod ends.)
That kind of thing. You should see it, if it's as bad you describe.
-- A