Sam - where have you been? Are you desperate? I reckon Tim or Snaf will have a solution. I believe KTM front wheels are all the same after 2002/2004 they had a smaller diameter wheel spindle before that...
Fit the bearing with locktite 641 (green) you can also use a centre punch to peen the mating surface to achieve a mechanical interference fit if it's really sloppy but locktite 641 will take up a push fit gap no problem.
__________________
Walk a mile in another man's shoes. ...and you will be a mile away... and have his shoes..