Color photocopies are pretty stable, at least a year, perhaps longer when light levels are controlled. The replacements are cheap, too! The size is limited to 11x17 though. Next best would be to find a color service bureau in your area that does inkjet output. The process involves scanning the original into a computer and then printing on a large inkjet printer. The images will look good, and protected by a clear laminate last for a couple of years. Size is limited to 50" by whatever length. I recently saw an ad for a piece that was 250' long. Cost is about $20/sq ft. Whitney Watson Exhibitions Designer Missouri Historical Society