Do you have 5.25" and 8" floppy disks that are spare, low-quality, degrading, or just generally in bad shape?

I'd like to take my floppy disk data recovery game to the next level. I have equipment, but there's no substitute for experience. Therefore I'm looking for loose collections of old floppy disks to practice on. I'm especially interested in working with disks where the binder affixing the media to the donut is starting to fail.

I'm in London; will pay shipping; can pick up disks around here as well. Boosts are appreciated!

@stepleton I've got a big box of maybe 50 old BBC Micro 5.25" ones somewhere. Is that the kind of thing?
@GypsumFantastic yes, that's just the kind of thing I'm looking for, especially if they are cheaper, lower-quality disks that are harder to recover! But to stress, I'm looking for disks to use for practice as I develop my technique, so while I would do my best, there's a chance that any data sent my way would be lost forever...
@stepleton They're not quite how I remembered. A few originals (education software) but mostly handwritten labels.

@GypsumFantastic Now that looks like training material, and quite a few more than 50 disks. I'll DM you an address.

My approach will be to sort them by manufacturer and type and then try them one by one. I'd like to develop some familiarity with the kinds of behaviour to expect from different makes of disk.