Here is a hard to find antique original, Seth Thomas Ding Dong strike Adamantine mantle clock in great working condition. It comes with a key but not the original key. It needs a double sided key for the fast and slow pin. It runs a little slow because I do not have the fast slow key.
Easily found, I do not know the size though. The key that comes with it will wind the clock and the chime side.
Great paper label still attached to the inside of the back door. Thanks and have a Blessed Day.
Update, I have a double sided key that works on this clock.