Anybody know where I can buy that onesie?
Yes you can find the download here. If your phone isn't rooted make sure you log out of Snapchat if you log into Casper, and vice versa. If your phone is rooted however, you can log into Casper with root access so you can be logged into both apps at once.
On Android, use the MEGA app (Play Store link), to download the whole folder.
You do not need an account to use the app to download stuffs.
Look I've done it here: https://streamable.com/z106g