Retrocity has gave you awesome idea. With old paper image you have save allot of work in a start. You can extract just the scratches with High pass and Color range to get one of the texture parts for overlay. You can fake paper damage with Clouds, G Blur and Treshold. For coloring I would use Hue/Saturation. Hope this will give you some idea :)

Tihomir

Open your mind and share the knowledge!