Simply Conserve G24D vertical PL 26-Watt EQ Single tube Cool White G24d-2 Pin Base LED Light Bulb (4-Pack) in the General Purpose LED Light Bulbs department at Lowes.com
Osram 13W Dulux-D 2-Pin G24d-1 Cap 840 [4000K] Cool White Colour Energy Saving Compact Fluorescent Lamp - - Amazon.com
2 Pin Base LED Replacement Bulb - Replaces 18-26 Watt- G24D Base Lamps - Ballast Compatible, 3500K
Earthtronics 12W 2-Pin LED Plug In Lamp 4000K Horizontal Beam LPD12M/G24d /840H
Philips 26-Watt G24d-3 CFLni 2-Pin Light Bulb Neutral (3500K) (10-Pack) 383232 - The Home Depot
E-Simpo G24d to E26/E27 Adapter (NOT GY24d)2 Pin CFL Socket Adapter 21.8mm G24 to E26/E27, GX24d to E26/E27 Lamp Base Converter,Rohs. 2P in Cross, Need Bypass The Ballast! (10-Pack) - - Amazon.com