Are you missing a stone from this piece? You can send your jewelry to some place like Perry Null in Gallup, NM (Jason the moderator of this site can give you more information on that), and they can find a stone to match. I’ve had numerous pieces of Native American jewelry fixed at different places out in New Mexico.
If you live outside of the Southwest I would be very careful about having your jewelry fixed any place in your area. I live in IN, and no one here has any idea on how to repair Native American jewelry. Check out this thread that was on here just a few days ago…Help - a jeweler may have damaged my turquoise.