are you just making it without any sound? just a straight led saber?
shouldnt matter. if you get a driver later, im assuming you mean corbins driver, you simply take out what you have and wire up the driver in place. if you want sound, then you hook up the sound board to the 2nd momentary switch. it acts like a trigger for the driver. so when you activate the led the sound should come on too. you have to hold the 2nd switch down when you hit the first momentary switch. and i think you do the same when turning it off, correct me if im mistaken.

in short, i'd say yes you could do that.