Steve Bertram of Bertram & Company.
http://www.bertramandco.com/Aaron Little.
https://www.facebook.com/amlittlebespokegunmaker/Dewey Vicknair.
https://vicknairgunsmithing.blogspot.com/J.J. Perodeau.
https://jjperodeau.com/ I'm sure there are others, but these four are a good start.