There was a time when a Jeffrey's dulcimer was about all one could get and he advertised in Sing Out Magazine, if I remember correctly.   There were a couple of other builders but nowhere like today. One rarely sees a Jeffrey's in this day and age.

Some players who use wooden pegs also use "fine tuners".   Little beads with a hole drilled in the middle are placed on the strings.   The luthier who recommended against the use of metal tuning pegs might be able to tell if that was practical on your daughter's dulcimer.

The Ozark Folk Center in Mountain View, Arkansas holds a dulcimer contest in connection with its annual Dulcimer Jamboree.   Four of the five finalists were under 20 years of age. Its kind of nice seeing young folk taking an interest in dulcimers. We might have to start junior and senior divisions to give the older folks a chance.