He could try the adapter route for £13, an adapter and use his own headphones.
https://www.amazon.co.uk/Griffin-Blu...th+transmitter
Some conflicting reviews, but I have one works perfectly.
Other than that, as he is an iPhone user, it's hard to look away from the air pods. I have had my share of headphones including the great noise cancelling Bose Q35s, but Apple really nailed it with the AirPods,.
There are better sounding headphones, and yes they are expensive, but for sheer convenience they are brilliant, and are great for handsfree calling too.