First of all, in this case, you are having it made for personal use which is allowed under the copyright law. http://www.copyright.gov/ if you have to argue with the people at the printing office, maybe you need to print out and take in a copy of the parts of the law that apply.
In fact, the copyright on the photo holds for decades after the person's death, so it would be a good idea to put the copyright notice on the edge of the image if it is currently on the back - this would require either using a photo editor or printing the notice in black or as white letters on black on a small piece of paper and positioning it on the edge when you make the photocopy. That may also help satisfy the printers.