+1. I am looking for this feature too. It would be great if the list of parent pages available as meta data could match the pages they have access to. If a user only has the ability to edit posts to parent page 1, then that would be the only parent page they could select in the meta data box.
The restrict list of parent pages code in functions or as must use plugin works in a simple setup, but is more difficult in larger deployments.
Thank you for your consideration.