I do not recommend to replace the whole amp.
If it's basically working, it's worth to rework it... so replace the electrolytics, replace the preamp transistors with low-noise-type (MPSA18 f.e.) and even more important replace the resistors. After that it should be a new game. See this video of us:
https://www.youtube.com/watch?v=xS-K653kJ7Y
Significant! Not related to bark but also important: Shield the AC and put it away from the audio signal!
If it's basically working, it's worth to rework it... so replace the electrolytics, replace the preamp transistors with low-noise-type (MPSA18 f.e.) and even more important replace the resistors. After that it should be a new game. See this video of us:
https://www.youtube.com/watch?v=xS-K653kJ7Y
Significant! Not related to bark but also important: Shield the AC and put it away from the audio signal!

