I have had great success with Bob's Gun Shop, FAX 501 767-2750. He has been in business since 1955. He use to be open to the public and I always enjoyed going in his store and talking with him. If he does not have the parts, then there are some other locations out there. Everyone I think has a favorite vendor.
Good luck with repairs. You may want to tell us about your HSc. It is enjoyable to learn what is discovered.
Jim