I've seen these at Barnes and Noble:
Here's a link.
The paper is brown and sometimes has little specks in it since it's recycled. I've only seen the smaller one but I'm sure you can order the large size online somewhere.
This one looks similar only larger and not wirebound:
Click for the link.
Hope that helps a bit. It's the only brown paper I've seen without having to make a custom one, and I've never seen a grey one, these are brown. Moleskines are more on the yellow side.
I'm cold as cold as cold can be.