Need rubber eye cup for Konica Minolta A2 viewfinder.
These are frequently lost and are fashioned of purest unobtanium.
When mine disappeared I bought a non-working A2 on eBay very cheaply and carefully removed the old eyecup from it and glued it onto mine, it also had the benefit of providing spare body covers, a lens hood, battery and a strap. A cheaper alternative is to buy a non-original replacement, see item number 220440673814 on eBay, or search for seller birthdayboy; the eyecups he sells are good, but it looks ugly and gets in the way as it isn't flush with the back of the camera.
Don't re-sell the donor camera if you buy one: sooner or later you'll need the flexible circuit board from inside it, as the one in your camera WILL eventually fail to power the viewfinder lcd backlight. The old camera will serve to show you how to dismantle and repair your original one. It's one of those jobs which is so fiddly and time-consuming that a professional repair is totally uneconomic.