The Wein cell is basically a zinc air hearing aid battery with a ring around it so it fits in the camera. My battery solution was to buy the Wein cell and a supply of the appropriate sized zinc air hearing aid cells (I forget the number, maybe 625?). When the Wein cell dies, I pop out the battery in the middle and replace it with the hearing aid cells. I have done this on my Yashicamat, OM-1, and Luna Pro with great results. Altough the batteries don't last as long as others, they are super cheap and readily available.