Hi folks. I just purchased my first Eureka clock. It’s been running and keeping good time with a 1.5 D battery. Can anyone tell me approximately when it was made? It has the original old dial which I removed but I can’t find a serial number on it. It doesn’t appear to be a marriage as everything fits up well with the case but I’m no expert on these clocks. It has the original old keys for the front and rear doors as well as a separate old key to regulate it. Any information would be greatly appreciated.