Different Header on Each Page

I have a WP theme that hardcodes a header graphic into the css and it is then displayed as a background.

The client wants to have a different header graphic on each page. It’s a small website maybe 8 pages.

My thought was to use CustomPress and give them a radio button to choose the header photo on the page.

My problems:

1. I don’t know how to access CustomPress fields in the page.

2. I don’t know how I would override the default photo in css.

Any thoughts?