.32 S&W ammunition is generally required only for older top break revolvers from numerous makers, S&W plus others. It can also be used in newer solid frame revolvers chambered in .32 S&W Long and several similar calibers. That is the reason for asking what kind of revolver you have. Not long ago it was fairly easy to find, not sure what its availability is today. AmmoSeek would be the best place to look if you cannot find a local supply. Or look at gun shows. Some dealers may be able to special order it for you.
Thanks for the help. The ammoseek suggestion was what I needed. I was trying to help a buddy who bought the revolver just because he likes old guns.
I've got a little history with a safety hammerless model that my grandfather had, but that's been about 60 years ago. By coincidence, I had just looked at two of those in a shop today.