Mario Hatzopoulos

Hello everyone, this is my first time on one of these Forums. But I recently bought a Cinemax Macro C-802 Super-8 and I've noticed I need a special battery for the light meter. Its a mercury battery and fortunately I still have the original piece that was in the camera when I bought it. Here's what it says on the battery: Brand: National Mallory Branding: H-3 D 3.9V (This is not a Button cell. This battery is about 2cm in height and about 1.5 cm in diameter) Country: Japan My question is. Do these sort of batteries still exist? Or at least a format of them so I can use my light meter again? Thank you for your answers in advance! :D