I have a clock just like this one, except that the face is worn from my grandparents turning the hands with their fingers. Mine also keeps good time.
I was told that it belonged to my g-g-grandmother. Like you, I'd also love to find out the manufacture date. The monetary value would be nice to know, though I will never part with it out of my family.
Mine used to have a glass that would close over the face, but it broke before it was given to me. I have the metal ring that once held the pane of glass, but it is broken off as well. If you have found any additional information, please let me know. My address is mike@mikesoutherland.com.