Amazon.com: Gikfun 12x12x7.3 mm Tact Tactile Push Button Momentary SMD PCB Switch with Cap for Arduino (Pack of 25pcs) AE1027 : Industrial & Scientific
1000pcs Tactile Push Button Switch Cap,micro Switch Button Cap,momentary Tact Cap Multi Color Fit 6*6 Switch - Switches - AliExpress
Round Tactile Button Cap For 6x7mm Tactile Switches Push Button Switch Cap Cover | eBay
GUARD R17-10: Protective cap for toggle switch at reichelt elektronik