Various brands of new 3.5", 1.44 MB, HD, IBM compatible floppy disks, as well as many reformatted disks. They are all fully functional and can be used for quick, portable storage. Since these floppy disks do not remain in the drive, THEY CAN NOT BE HACKED.
$1 ea (6 for $5) or 12 for $10. I have many disks, so let me know how many you would like.
These disks are great as teaching tools, marketing tools, props, decoration, and art, in addition to their actual intended usage as computer data storage. There are also many arts and crafts possibilities using these disks. Google "floppy disks as art". Here are just 2 examples: