My ball joints looked exactly the same as yours and they had big time play in them, so I decided to replace them. Upon expecting the front end, I noticed that every part was basically worn out. So I ordered everything, lower ball joints, upper control arms with ball joints already installed, tie rods, drag link, guide rods, control arm bushings, and idler arm bushing, all Lemforder. I basically spent close to $550 in parts alone. If i only had the ball joints replaced at a reputable independent MB mechanic, it was in the neighborhood of around $400. I couldn't imagine what the cost would be if the front end was totally rebuilt at the same shop. The hardest part of labor for the front end was removing and installing the front coil springs. Everything else was easy. I did bring the the old lower ball joints and control arms to the MB shop to have them press out the old ball joints and install the new ones, cost $40, money well spent. Once everything was put back together, I had a wheel alignment done and everything is so much better!!!
My front end is so much tighter, especially when the suspension is articulating, in turns and when going over bumps.
I highly recommend getting your front end rebuilt, whether you do it yourself or at a shop, and use either MB parts or Lemforder, and you will be set!!!