Is there any way to get a replacement grill/mesh?

I had the same issue as apparently many others of one ear being much quieter than the other, and took the grill and filter off in order to clean, but had to get up to answer the phone and I must have knocked it or something because it was gone from my desk.

Is there anything that can be done for this? does anyone know if there's some way to get a use-able replacement or is this basically just scrap now?

I'm not too bothered about the water resistance lost since I knew I may lose some of that from taking it apart, I just want to be able to use this piece of tech I have lying around and leaving an empty hole doesn't seem wise