The integrated circuit of this amplifier is not very common today. The output transistors can be TIP31 and TIP32 in heat radiators. The circuit is from the 1977 National Semiconductor Audio Handbook.
This circuit was found in a 1980s documentation. The IC is the 7400 and should be powered with 5...
The function generator XR2206 is not very easy to obtain, but if you get one you can assemble this...
This circuit converts a 12 V continuous voltage from a battery into an alternating voltage of 110...