From: Josh Dersch <derschjo at mail.msu.edu>
(As a related aside, is there *anywhere* one can get
hard-sectored 5.25"
floppies these days?)
People have been known to make their own 5 1/4" hard-sectored disks. I
don't remember the details, but the basic idea was to take a 5 1/4" disk
drive to hold the disk, make an index wheel for the holes, add a hole
punch, and then just add time.