Kenwood National Parts: (Pacparts): http://www.pacparts.com/
There are others, both east and west coast.
(If shack is separate room, a door lock or even a catch way up high is a good thing. When the shack is in a shared room, consider locking cabinet, rolltop desk, etc. to keep those little fingers away. -- Remembering the ham whose little grandchild actually managed to fire the rig up and use the PTT, just like grampa! We listened to that on 20 meters for over an hour one afternoon, poor guy must have been embarassed at the least if he ever found out. Then again, the kid was a lot nicer than other things heard on 20... )