Downbeats sells a “smaller fit” set that I like for their noise dampening in stores and other crowded settings, and they don’t hurt my ear canal like a lot of in-ear plugs. They’re less than $15 on Amazon.

If the scar is new, massaging it frequently (using some type of serum or oil to reduce friction) can help reduce the size and how much it is raised.

If it’s more than a year post-injury, only a plastic surgeon could help.

(Info from brief training on scar management in grad school and doctor’s advice after having stitches.)