There's the Victorinox Flagship Store at Rue de Marche 2. No alox, but they have most of the rest of the range. They also have a little workshop in the basement, although I've never seen it in use.
There used to be a much more interesting SAK shop on the opposite side of the street, but it closed down a little while ago - perhaps due to competition from the bigger, newer, shinier (and emptier) Victorinox store.
But if time is short I'd give Geneva a miss. The region has hundreds of more interesting places to visit.