I'm not 100% satisfied with this, but i can't make the pic look any better than this ._.
It's funny how there is only one single scan of this picture on the web (at least i couldn't find any alternative)

I see why, there is an apparent texture to it visible in the darker areas

The problem with this texture is, if i start to remove it, the picture starts losing details. There are most likely other ways to do this but i don't have much experience with fixing images so....

Maybe someone else manages to remove the rest of the texture. Looks good enough as a wallpaper @1680x1050 for me :3

http://moepic.logdb.net/chkbbs/remodk/0006084620090307113609/ >@1680x1050
http://moepic.logdb.net/chkbbs/remodk/0006067420090304204059/
fixed versions

The problem with the 1680x1050 one you linked is, as well as with another wall @1920x1080 i saw, the aspect ratio. The whole pic is squished to fit the resolution.

The other one has a clear color change where the creases used to be, so my edit is actually better. Just open both pictures side by side and you'll see what i mean. Also, petopeto managed to fix the noise far better than me, see the parent post.