Looking for a mechanic/garage in the Watford Rickmansworth area

[Mistry200k]

Hi all, pretty new to this scene, I have a 2001 C Class 200k Estate and have recently heard a knocking noise from the front of the car, after reading various post it seems to be the front suspension bushes are worn. I took the car into my local mechanic and he has told me that I need to replace the front, rear and top suspension arms. I asked if he could just replace the bushes but his recommendation was to replace the whole arms. Parts alone for this are coming to about £450 and then his labour on top.

He's not Merc expert so wanted to try and find someone for a second opinion. Does anyone know any decent garages around the Watford or Rickmansworth area I could try.

Any help much appreciated