BUY a1294 https://www.utsource.net/itm/p/1903002.html

Package: TO-3P Manufacturer: Sanken Description: A1294 is a high voltage power transistor manufactured by Sanken. It is a NPN silicon epitaxial planar transistor with a maximum collector-emitter voltage of 800V and a maximum collector current of 10A. Features: High voltage: 800V High collector current: 10A Low saturation voltage High frequency operation Low noise Applications: High voltage switching applications High voltage power supplies High voltage amplifiers High voltage inverters (For reference only)