DVD drive for Studio 1537

Hi,

  I have a Studio 1537, and the DVD drive has stopped working.  When a disc is inserted, it sound like its being chewed up, and the drive makes a "click-click-click" sound on startup and wakeup.  I'm pretty sure there's not an OS/driver fix for this kind of thing, but I can't find any information on a replacement drive.  What are the specs for the drive/where I can get a replacement?  The Dell parts locator will only show me hard drives.  Is this some kind of unreplaceable integrated drive?

   Thanks.

           Seth