Wasn't sure where to post this, so I'll dump it here and it can be moved if need be.
I was sick of digging around forums, Google images and random webpages trying to find the genuine part number for the odd thing.
Managed to stumble across this site: http://opposedforces.com/parts/
Covers a few main models; Forester, Impreza, Legacy, SVX, Tribeca.
Source: http://legacygt.com/forums/showthread.php/subaru-oem-parts-catalog-online-exploded-views-opposed-forces-130411.html