Apple ID tied to defunct email address and protected AAC audio files

I have music purchases that I made via iTunes 15 years ago that were tied to another Apple ID using a cloud-based email service that no longer exists. So I have no way of accessing the email account in order to follow the reset password pathway.

Songs that I purchased with that Apple ID were accessible and working on my playlists until I purchased a new MacBook Pro last week and moved my iTunes library from an external hard drive over to the hard drive on my new laptop. Now those handful of songs are requiring an authorization of my MacBook Pro that I can't provide because of the old Apple ID that is now defunct.

The songs are no longer in the iTunes store (or I would simply re-purchase them), but I have the protected AAC audio files.

Is there any way for me to get the purchase authorization transferred to my current Apple ID (even though I can't access the email address tied to the old Apple ID)? Or, alternatively, is there anything else I can do to re-authorize the protected AAC audio files?