In our other thread where we've been talking about SVX cages, I went back and posted a couple of the pictures that Joe kindly took. Might help you to see what you need.
SVX / Legacy radio compatibility (post #10)
and here's his picture of the inside of the cage:
(click on the thumbnails to see larger versions)
Here in the states, SubaruParts.com lists part numbers for many of the components that make up the cage and door (as well as the whole assembly for $$$). This is for our LHD cars, but it will give you an idea of what might be available...
You may be able to order just the bits you need from a local Subaru parts source. It's possible they could even have the correct coloured door. I suggest asking up front whether they'll let you decline it if it doesn't match
[a little later I'll try to decipher the cryptic part descriptions and make a list of what each part number is in English, and then update this post]