How to make my macOS user avatar also my Apple ID avatar?

I changed my avatar on macOS to one of the defaults, thinking I was only changing the user avatar. When the new avatar started showing up on my other devices, I realized I had actually changed the iCloud (Apple ID) avatar - and the user avatar is still the one from iCloud.

How can I return my Apple ID to the previous avatar? (Or, copy my user avatar into my Apple ID?)

I don't have the original image I used for my Apple ID available.

Thanks in advance for any help you can offer...