power steering problem

MY PUMP NEEDS REPLACING, 2001 E320CDI, AND ITS ONLY WORTH A SECOND HAND PUMP, I RESEARCHED THE PART NUMBER AND GOT 2! 0024667101 AND 002467401 THE DESCRIPTION OF EACH SAYS IT FITS MY MODEL BUT WHY WOULD THEY MAKE 2 PUMPS? I TAKE IT THERE IS A DIFFRENCE? ANY HELP APPRECIATED.

Hi all, I have a problem with my A160 CDi, year 2005. It started about 2 months ago, when power steering got bit heavier. Not completely out of service, but evidently much heavier than it used to be. It usually happens after cold start and gets better when driving. For info, the car has...