Here is a video showing the button actions, and since I was up on a scaffold I recorded the chiming from above.
I printed a box for the NodeMCU and for a button. (My first ever 3D print!)
The button has an LED to give some feedback about the mute state: one flash - muted for 1 hour, two flashes - two hours, etc.
The button box has a magnet to stick on the steel frame of the old house. The button will be put on the column near the clock.