Get in touch with user "Yoda". He's been supplying a repro clock for several years. It's an exact fit with the same look, an internal backup battery (keeps time in case of disconnected power), excellent timekeeping accuracy and easy DIY instructions. No lens. See the thread below for the latest info.
He recently confirms the clock is still available. He replies promptly to PMs sent from this forum.
Good guy. Tell him I referred you!
https://dmctalk.org/showthread.php?20093
(Post #8 in that thread points to a larger string that in part features the "Yoda" clock)