Huh. I got this email and it does seem to be sent by paypal, but the To field is not my email address or one I know. I checked my paypal account and there's nothing about this. Any idea how I got this email? I'm assuming it's a scam.
I figured out the scam and wrote it up here: https://www.reddit.com/r/Scams/comments/1j9u5wp/legit_signed_email_from_paypal_but_833_6662587_is/?
Basically, they set up their merchant account with a merchant name that is literally, "If you do not recognize the seller, please contact.." hoping you don't notice all the other wrong details. But this does get them a legit email with a digital signature signed by the real paypal.com, which they forward to you.
If you have a fediverse account, you can quote this note from your own instance. Search https://mastodon.social/users/AlSweigart/statuses/114151385316920505 on your instance and quote it. (Note that quoting is not supported in Mastodon.)