Occasionally NDSMR gets asked about repair service on Hammond, Leslie, & Rhodes equipment. Though some issues can be addressed, specific knowledge on vintage keyboards can be out of the area of expertise.
I’ve recently visited Boss Organ in Somerville, MA & definitely recommend checking out this one person operation! The owner Tyler is extremely knowledgable on the inner workings of the equipment he services along with being helpful & friendly. In addition to repairs Boss rents organs, sells parts/equipment, & does customizations.