My w124 also had the same clunk problem when turning the steering wheel to the right and returning it to the center at a stop. To fix it I went to the auto repair shop at 10 am in the morning today. The mechanic raised the car and found out that the front tires also had a loose left to right movement which was not good.
Then the mechanic pulled out the #1, #2, and #3 part from the picture above. All of them are steering components and all of them had a small tire rod mounts on both ends (see the picture). The mounts were loose and had been easy to twist and turn.
He then disassembled the mounts on both ends of those parts by pushing the bolts in from the back where they have a cover using a hydraulic compressor. There is a plastic that keeps a ball like looking tip of the bolt in it that was deteriorated. He then replaced the plastic pieces inside the mounts, put some WD40 inside and sealed them using the hidraulic compressor to squeeze the back cover to the plastic and then used the hummer to bend the sides to mount the back cover .
All of that took 2 hours and I ended up paying $15 in total. The mechaninic guaranteed they will last at least 50000 kms.
If you come to Uzbekistan I will help you fix your problem for $15
A test drive showed no more clunks, tire vibrations at any speeds under 140 kmh.