Bluex Bulbs BlueX LED 60-Watt EQ 4-in Warm White Miniature Bi-pin (t5) Circline Type A or Type B LED Tube Light Bulb in the LED Tube Light Bulbs department at Lowes.com
Amazon.com: CMLAMPLED F15T8 3000K LED Tube T8 110V AC 18inch/18 Length 7W 3000K Warm White T8 LED Replacement Tube Light (6 Packs) : Everything Else
Vintage Hardware & Lighting - 4 Foot LED Replacements For T8 Fluorescent Tube (48-T8-LED)