Quantity   Component name
2 × 2N5551 (or other) transistor
2 × CD4069UBE (or other) Hex Inverter
1 × ATTiny12 (or other) microcontroller pretty much anything 4Mhz or better will do as long as it sample I/O fast
5 × 10K resistor
2 × 1K resistor
1 × LM7805 linear voltage regulator
1 × 100uF 100v electrolytic capacitor
1 × 10-15V variable voltage power supply One of those cheap boost converters with USB input will do