Cuckoo clock 8 day oompah band

Hi, I recently purchased this eight day oompah band Cuckoo Clock at my local flea market it appears to be a excellent condition but missing one bandmember and its pendulum also unknown if it works or not as I think the 8 day weight are the wrong weight clock only works when I pull on the weights the three weight are (2 1260 grams )( 1 is 1280 grams ) I think ? 1500 for this Clock can anyone tell what weights I need to get this clock working I took pictures of the movement for you to see the movement is regula I would also know how old this Clock may be I serve no date but I think 1980’s? 1990’s? Thanks.