I myself form the base for the magnet of the desired shape from air-hardening modeling clay. I paint the portrait with acrylics and then cover it with several coats of glossy protective varnish.
The magnet is very light and strong enough, but it must be protected from falling from a height.
You will receive a photo of the finished portrait from me. If necessary, I will make all the corrections you tell me about. Only when you confirm that you are satisfied with my work, I will send the package.