2 X 25w Lava Lamp Light Bulb S Type E17 Base 25 Watt S11, 25S11, 25S11N, S11N25 | eBay
Feit Electric Soft White Intermediate Base (E-17) Dimmable Incandescent Light Bulb in the General Purpose Light Bulbs department at Lowes.com
Snapklik.com : 25 Watt Lava Lamp Bulb,E17 Intermediate Base The Lava Original Replacement Bulb For 14.5 Inch Glitter And Lava Lamps,120 Volt Lava Lamp Replacement S11 Bulbs,2700K Warm White,Pack Of 6