You tried giving Apple a call? Pretty sure they'll replace one.

Sorry airpods dont work in my ears

but I wonder if there is a online service for 1 earpod replacement could be a business there 

Apple sell individual replacements

https://support.apple.com/en-nz/airpods/repair

Thanks, looked into the Apple replacement, it's hard to justify $169 on the bud. Prefer to pay a little less for one second hand. 

i gave up on super expensive ear buds a while back. Just roll the $30-50 lenovo ones from ali express. After you have one go thru the washing machine you kind re-evaluate the point of $250+ tiny electical devices :D

Someone here put me on to Soundpeats as I wanted a similar fit (not in ear canal).  They have been brilliant, at a budget price  

https://soundpeats.com/collections/all-products/products/soundpeats-air3-deluxe-hs-wireless-earbuds