Hm... well, there are all sorts of different Laguiole manufacturers. Obviously, the Forge de Laguiole knives are kind of expensive, but there might be cheaper brands out there. She should stop by Armes Bastille at 61, rue de Lyon. It's just down the street from the Bastille métro stop (and a few blocks away from the awesome Viaduc des Arts.) Alternately, there is a store called Dune in one of the shopping areas on the Champs-Élysées. It is kind of silly, though, selling all sorts of crazy stuff (supressors, even!) Her best bet is Armes Bastille; I knew it was a decent knife shop when I saw them selling sebenzas.
Paris me manque...