Hilitchi 24-Values 2N2222-S9018 / BC327-BC558 NPN PNP Power General Purpose Transistors Assortment Kit - Pack of 840: Amazon.com: Industrial & Scientific
Npn to Pnp Level Converter,8-Channel Npn to Pnp Signal Converter, 8-Channel Optically Isolated Module for Npn to Pnp Level Conversion Wide Voltage 10-28V: Amazon.com: Industrial & Scientific