I finally managed to get a used LHD part, it looks good at first sight, but I wonder if there is a way to check whether is still functional before getting it into the car (I also found out what that cylindric shaped section is good for - it is the steering damper, that used to be a separate part on earlier models and I guess it is also responsible for the play that I am facing).
And the second question is how I could get it into the car? Accessing the lower bolt where it is attached to the steering rack is no problem, even on the V12, but the upper part, which is attached to the universal joint is not accessible from below the car, it's behind that grommet that leads it inside the body. Would it be necessary to remove the steering wheel (and maybe even the whole dashboard) to access it from inside the car? Or can that grommet be fiddled out and than the upper bolt is easily accessible even being inside the body (which I think is almost impossible with the engine being in place ... at least the left exhaust pipe + manifold has to be removed)?
Edit: Or does the drawing from the parts catalog really tell me that the lower steering column is simply plugged into the universal joint but not additionally fixated by any bolt?https://parts.jaguarlandroverclassic.com/parts/index/part/id/C01.918.91857.91857283.918572834842/brand/jaguar/