I did indeed try the vertical banding reduction script, but it introduced more bars. I'll admit that I did not fine-tune the settings, though -- that's next.
Instead, I painstakingly used CCDOps to run their fix on every file -- 31 of them. I wish I could get CCDBand-Aid to work!
I feel foolish, too -- I just scrolled to the end of this topic without looking at the first post, the one from the author of CCDBand-Aid! I'll try to get in touch with him directly.