The only numbered notebooks I've seen are daily planners. Moleskines are leather, though not sure about the quality.
Edit: Saw these in comments: http://www.leuchtturm1917.com/de/content/startseite
Edit: Saw these in comments: http://www.leuchtturm1917.com/de/content/startseite
Moleskine notebooks look promising, except they aren't really leather and don't have pre-numbered pages. I guess I can number the pages myself, but it would be nice to already have it done.