With most cameras that took the old 625 mercury cell you can substitute the very cheap 675 zinc air hearing aid battery. I've done so in many cameras.

In fact, I suspect the Wein cell is nothing more than a 675 zinc air hearing aid battery fitted with a metal collar to bring it up to the diameter of the 625.

A packet of around half a dozen 675 zinc air hearing aid batteries costs around five bucks. Each cell will last up to 6 months once the tape is removed from the air vent.

I've read some tests on the web that indicate the output characteristics of the 1.4 volt zinc air cell is much closer to that of the original 1.33 volt mercury than anything else on the market.

The only hitch may be the smaller diameter. I've never found that to be a problem. If it is tweaking the tension of the battery contact spring in the camera's battery compartment will fix it.