Not true, they can be sourced from
@cruiseroutfit though they are massive (like the size of your hand), and you will probably need a press to install them.
I believe these are them, but just call the parts dept to confirm.
Toyota Land Cruiser Ball Joint
cruiserteq.com
I am not sure this is actually your problem though. It sounds more like a alignment issue. Is it only happening at basically full lock?
Edit: I see you changed the UCAs not long ago, and maybe it is the angle of this picture, but the the center line of the UCAs compared to the coilover looks a bit screwy. It would seem like you would have some odd caster issues considering where the upper ball joint is located, or again maybe just the picture angle?
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