Ok. I know this will draw out the clever comments, but...
I have just acquired a bunch of retired water-polo caps from the local club. I have been using one for years for summer surfing and windsurfing; great for my Pacific Island surf camp trips. Great for those who are a bit thin on top as they cover a large area of the head, ears included. Ear covers do not restrict hearing. I know they are not cool, but are very comfortable and super sun safe. Am happy to give you one for the cost of the postage, probably about $4-5 at a guess. I have a red and several blue. PM me if you want. cheers