Different Backgrounds for Different Cameras

I am attempting to create a Blender scene of a 1930’s street corner, using 3 actual photographs of that corner, as well as a city planning blueprint, from that time. I have successfully loaded one of the photos as a background image, for the first camera. That, and using the blueprint as a background for the top ortho view, has helped me to place the first few key objects.

Now, my question: I would like to place 3 cameras, to match the views in the 3 vintage photos (for construction purposes). Is it possible to load each camera, with a separate background image? Blender 2.68 only gives me the option of “camera”—loading the same background image into all 3 cameras.