Sony WH-1000XM4 Noise-Cancelling Wireless Headphones - Spares and Repairs

These headphones have unfortunately been slightly damaged on one side (water damage). The noise cancelling still works perfectly on both sides, but the audio only works perfectly on one side. The other side has audio, but it is not as smooth. I have used this pair for a month as they are now. So they are still usable, just not ideal! This set of headphones will be great to use as spare pieces. Or could easily be repaired. There are YouTube tutorials online, but Im a uni student, so I don't really have the time. I also got a new pair for christmas :) so I no longer need to use this pair. A new pair goes for £184ish. A second hand pair goes for £120ish. I'm not sure what to put this pricing as, so I'm open to offers!