General Atomics is a beryllium vendor site for 1944 and 1950 so workers are eligible to file Part B claims.
Fansteel Metallurgical Corp. performed beryllium work for the Manhattan Engineer District under Contract No. W-7425 eng-27 for the fabrication of beryllium into sintered shapes and for the manufacture of 600 bricks for delivery to Los Alamos. Fansteel also worked with "approximately 150 pounds of nominal grade beryllium carbide powder" for use in the Nuclear Energy for the Propulsion of Aircraft (NEPA) project. This work is reported to have occurred between April and June of 1950.
DOE's Legacy Management has a webpage for Fansteel.
DOL provides Part B statistics on Fansteel.