Thanks - I picked up some gaffer's tape at the photo store.
The leaks are minor, just along the bottom of the camera, in the margin of the film that would normally be blank. Very rarely intrudes into the image area at all, so.... Some gaffer's tape and rubber bands helps, but doesn't eliminate it.
I'm not going to worry about it anymore till next winter, when I have time to do more about it. Meantime, I'll just use it.