I think that you could contact a local guild and get the name of a long arm quilter in your area. There are some very talented quilter's in your area. Ever go to one of thier shows?
It will depend on the design that will be done on it and the amount of bobbins that are used. Some gals charge by the square inch. Around here for an allover design for a queen is about a hundred and fourty dollars. But, I am thinking that might be a lot more because of buying the silk threads that will be required and the specialty designs that it deserves.
That is a family treasure fo sure... goregeous!