Silicone spike light bulbs - I've kept these for the last 15 years or so. I don't know where my father ever got these. The purple is burnt out but the rainbow
Pearlized Silicone Light Bulbs - Paxton Hardware
Light Bulbs – Old Farmhouse Primitives
Silicone Light Bulbs: Coolest Candle Bulbs Ever - LightLady Studio
Silicone Dipped Clear Light Bulb Electric Candle Lamp 5w Replacement Country Primitive Lighting Décor - - Amazon.com