Drivers side steering rack movement?

.........in a nutshell, as an ex VACC Vehicle Examiner, I can throw some light on your dilemma, which may render your vehicle Unroadworthy and possibly unsafe/dangerous.
"RWC standards require no excessive movement in any direction, except normal operational direction, of any steering or suspension component"
So, if any Bush, Bearing, Ball Joint, Insulator, Main Component, Minor Component, or Mounting, is not within "specs", it must be replaced. Alignment Geometry must also be within "specs".
Only when all the above is done, to Industry Standards, to front and rear ends, will you be problem-free.
Usually, only a Qualifed Mechanic has the skills and knowledge to satisfy Standards.
A non Qualified Mechanic can learn, with correct tools, study and practise, to achieve Standards.
Hope this helps
 

Probably the plastic bush behind the tierod