The package will no doubt be too big for Priority mail shipping, and if the size is too large, it may not be mailable. At that point, a freight company might be your best bet.
But what does his response to the mysterious Mirror of Erised tell us about what's to come? Thick woollen socks. That's what Dumbledore tells Harry he sees in the Mirror of Erised during their first ever face-to-face conversation in Philosopher's Stone.
Because Eren's Titan, the Attack Titan and one of the 9 Titans, has the ability to see the past, present and Future! When Eren kissed Historia's (the descendant of the Fritz family who are the creators of the Titans), he actually saw the past of the Attack Titan holders.