The dial face is no big deal. You can easily make that using PowerPoint.
Use 3M art spray to fix the new face to the time plate.
Similarly make and print the clock hand extensions on suitable colored art deco card stock, shorten the OEM clock hands using aviation/metal snips then fasten the printed art deco extensions suitably to the clock hands using art deco glue.
Instead of f'n around with a mechanical POS like what youve show, just write a software application that demos an animated clock face, flashes appropriately the symbology with option to speak the time increments. Make it programmable/modifiable - different interesting faces, time increments, add animal sounds, etc, the sky is the limit.
You might even be able to market the software.
PS: Come to think of it, you could actually use the animated presentation capability of MS PowerPoint to build a suitable demo as described above (even having attached audio files for periodic time announcements).