Amazon.com: UltraPro Porcelain Light Socket with Outlet and Pull Chain Light Fixture, Light Bulb Socket, Medium Base, Grounded Plug, Indoor Lighting, Mount on 3-1/4” or 4” Box, UL Listed, White, 18305,1-Pack :
Westinghouse Lighting 7001000 Porcelain Threaded Socket with Metal Shade Ring, White - Tools Products - Amazon.com
Medium Base Porcelain Sockets w/Mounting Brackets (3 pcs.) — MonsterFastener