If you visit shop.zoeller.com we have replacement parts for a variety of models. The M53 Revision D is there as well: https://shop.zoeller.com/serviceparts/serviceparts/products/53-0001-revision-D
Call Zoeller at 778-2731 it should tell you a 24 hr # to call they will help you. If u do not for some reason get tonight call and ask for customer support tomorrow
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