NOrh SE-9 Single ended EL34 pentode for 9 WPC
Almorro A205 6BQ5 Single ended 6BQ5 5 WPC
Yamamoto 45 Single ended triode 2 WPC
Just to name a few, these are very good amps with horns, I use them to power the entire system though.
For more power, try the Cayin push-pull EL34 for 35 WPC
Ron