Alignment disks, and the creation thereof

Back in the day, I had a couple of friends who landed jobs at Jugi Tandon's little "R&D" operation on Coleman Rd. near the San Jose Airport. Most of what they did was come in after 10 AM and leave before 4 PM (with the exception of the receptionist), but there were one or two interesting things there. One was some sort of servo writer/calibration rig for hard drives. Basically a pneumatic piston (powered by a tank of nitrogen) rigged up with a laser interferometer, all mounted on a 4" thick slab of granite. I never did get the scoop on what was going on exactly, as we left for a beer-filled afternoon and the subject never came up. But heck, an enterprising hobbyist could create his own calibration writer by salvaging the positioner out of a CD-ROM drive or perhaps the head and positioner both out of a 5.25" hard drive. Floppy drives aren't rocket science. But it's the media that I'm most concerned about. Anyone know where to get floptical media for my 20 MB Insite drive? Or some 6MB formatted blanks for my Drivetec? Or some 3.25" media for my Dysan drives? Cheers, Chuck