Have a look around some of the US Forums for a username of "subie gal", she used to work at SubaruGenuineParts and had a good reputation for getting parts for Subaru owners.
From what I just found on Google SubaruGenuineParts has closed down, so unfortunately I don't know where "subie gal" is now working. Somebody in the USA may know more than I do about her whereabouts, she may also be able to point you in the right direction.
Here is a link to her Facebook page, I don't use Facebook...
https://www.facebook.com/TheSubieGal/