I was looking in eBay, and found a Seller who is selling a lot of (75) used 8" single-sided floppy disks for $19.95, (plus $32 for shipping). Some are in plastic cases, some are Original Software Master disks, and (6) and Genuine Shugart Single-Sided Analog Alignment Disks.

http://www.ebay.com/itm/75-Vintage-C...sAAOSw1VRZilSL

If you are still using single-sided 8" floppy drives, these are the alignment disks that are used with a 100Mhz Oscilloscope (and a exerciser program or drive exerciser) to align single-sided 8" drives. The original price from Shugart was about $100-$150 each. They have not been available from Shugart since Shugart went out of business in the mid-1980s.