It was. Even in good shape, it would occasionally crack over. The arch height was only 1.5" (the length of the opening from the base to the lip of the chime). Most full size whistles have a 2" arch height. You need to raise the arch height as steam pressure goes up. I have a Pennsy 3-chime that must have come from something big as it has a 2 1/2" arch height, and doesn't sound too spiffy at 180-200 lbs.
I've since found out the Reading 6 chimes were only used on one class of Reading passenger engines. So, there were only 20-30 of them made.
I tried to fix the Reading a few times, but I could never get the damned thing apart to make a new throat plate.