Originally Posted by Little Darwin
Actually almost any steerer tube for a 1" headset is less than 1" I believe the 1" is the head tube size.. I think yours is the most common size, some especially Schwinns and French bikes have different diameters by a mm or two, but almost any threaded fork with a long enough steerer should be fine for you... You could also move to a 1" threadless by replacing your headset.
If the bike needs a 298mm threaded steer tube, a 300mm threadless will not be long enough to accommodate a clamp-on stem in a threadless mode. Remember, this is a 67.5cm frame!!!