I believe the front half of the driveshaft. P.N. 28321 through subaruparts.com
I had my car checked out by a subaru mechanic because of steering wheel shake off and on. He recommended I replace the drive shaft assembly. Something about the u-joint leaking etc... I don't think the link I was directed to is what I need to know since it says right and left axle. Sorry for the confusion. I am so uneducated with most of this. Thanks.
Mike