An oddball request, but here goes. Do you have an old Commodore scientific or special-purpose calculator? These are normally either black or brown in colour, with more buttons on them than normal calculators. Maybe you have one lying around in a drawer, etc.? These were made in the 1970's and will either be powered by an PP3 battery or be sealed and rechargeable.

I have a number of these that I'm trying to restore, and as they are battery-powered, if not used on a regular basis, the battery dies and leaks inside and corrodes the parts inside. I'm hoping to salvage enough parts to keep some of them from becoming landfill and polluting the soil. The photos are to show what these look like

Commodore Calculators (North Chelmsford, CM1)