I recently stocked up on both 5 1/4"dd and 5 1/4"hd floppies so I have enough for my other retro computers, I have Nascom 1's and 2's, a trs80 model 4 and I am considering building a Nascom CP/M system which might use 8", 5 1/4" and 3 1/2" drives, I have an 8" drive but no disks yet, I also have Amstrad cpc's and plus's with 3" disks.
I have a bare 8" Winchester drive that has a capacity of 8MB, but it is not worth trying to do anything with it.