You can also see if you can borrow a case from another harpist in the area. I have done that several times when I needed to ship my harp to different places because I don’t own a case myself but I know a couple harpists who have a case that fits my harp.
There is a company in LA that will make a case for you, and it should be a very safe design to use. I think they made one for Marcia Dickstein. It isolates the harp in foam, like a double-bass case does.