This circuit is from old documentation, but it can be implemented with more modern equivalent components. The transistor can be the TIP31 with a heatsink and the 1N4002 diodes.
We found this configuration in a documentation for radio amateurs from 1974. The circuit can be...
Texas Instruments' low power operational amplifiers OPAx196 can be found on Mouser Electronics....
This low power amplifier circuit for speaker or phone is from the Philips Databook of 1990. The...