One advantage of fluorescent bulbs is that they last very long and therefore are cost efficient. The brightness in this bulb amounts to 4 100 lumen.
From Amazon
T9 Circular Flourescent Tube 60W - Colour Cool White- 840 - G1OQ Cap
LED Bulbs
Bell Circular Lamp 60W G10q Cool White - BL04197
Big on Electricals
Bell Circular Lamp 60W G10q Cool White - BL04197
Lamps 2U Direct
60 watt T9 Circular Fluorescent Tube Colour 840 Cool White