To Make a Hero by Randall Garrett

There were others in Taun to be cured. When Yon the Fisher awoke later in the day, he was still a little weak, but his pains were gone, and he declared that he was much better. As soon as word got around, the other seven men who had been stricken begged him to come.

Hale came, but he explained that -- naturally -- the medicine cost money. Crystals would do.