Many Fnacs in Paris! I would recommand Prophot in the 9° they have everything.
To have the films developped, call me when you are in Paris (06 59 99 19 07 / 01 42 40 17 13), a friend of mine does an excellent job!

Ps: by the way, my wife, who is working at the Musée d'Orsay, just came back from Australia!