It looks like gastroenterologists specialize. how do i find one that might do hiatal hernia + acid reflux surgery?

They don't operate: Under medical specialties, there is training program in GI diseases. These clinicians are the gastro enterologists who treat and handle the diagnosis of GI disorders such as Crohns disease, Ulcerative colitis, bleeding ulcer disease and are the one who do upper and lower GI endoscopy. Surgery of the upper GI tract is performed by general surgeons who can handle reflux and hiatal disease.