You can use any general purpose low power Transistor:- 2N2222, 2N3904, 2N4401, S9013, S8050, BC546, BC547, or similar NPN transistor
Diodes; just about any general purpose, switching or other low power diodes, can be used for these circuits, however Schottky diodes have lower voltage drops and work very well:-1N4001 to 1N4007 series, 1N914 to 1N4448 etc..Â
1-6 White LED 5MM 20ma each or you can use colored LEDs if you like.