Digging through my reference files, I found this gem. I did convert it to a wind-up clock because it just felt right.
Verts - 9,531
Textures -
1x2K (Clock)
1x1K (Glass)
OBJ, STL, FBX and Blend files
3D Metamec Atomic Clock model
For personal use and one commercial project (up to 2,000 sales or 20,000 views).
One copy to be used by a single user.
One installation by a single user.