Ditto what Larry said.
When you push and pull on the wheels at 3 & 9 o'clock feel for looseness. If there is, look for loose joints at the tie rods and drag link. When its bad you'll see them "hop" up and down because the ball joint is loose in its socket. If the boots are busted on any of the ends I'd replaced the entire assembly (some will suggest replacing only the boot or only the end under some circumstances).
In extreme cases, the linkage may tight but one or more of the ball joint studs may be bent if the vehicle has had any sort of accident, etc. In this case, the ball joint stud may act as an eccentric cam and the toe setting may change after an alignment.
If you have doubts, you can replace everything. The tie rods are about $38/ea, the drag link $48-64, &idler arm repair kit is about $28-50. Changing those parts requires alignment.
What makes you think the steering gear needs replacement? Generally they last the lift of the car unless it was overtightened to have < 10 mm play at one point. If its too loose, there is an adjustment. Some shops change one part at a time to keep you coming back.