PROPTECH on hartlebury industrial estate.
they make all sorts of shafts.
you may get away without resorting to expensive CV joints and be able to use UJs, as long as the angle the two universal joints run at is more or less equal
then the output flange will have a constant rotational velocity even though the centresection of the shaft will not.
This is how RWD car propshafts work without UJs. If the angles are differing by a more than a few degrees then use CV joints rather than hooke joints(UJs)
proptech will be able to advise you.
I am usually not as green as i am cabbage looking.