I have a couple of padlocks I picked up for dirt cheap at a corner store. They're no-name "Made in China" locks. One is smaller and looks like a luggage lock, the other vaguely resembles a master #5, but a bit smaller.
Both locks said "Disc Tumbler Lock" on the packaging, but I find it doubtful you'd find something like that for $5.
(This is the weird thing) The "front" of the keyway, the little plate with the keyhole in it, just turns freely, even without inserting anything into the lock.
The keys to both locks have identical wide, deep cuts with rectangular "hills" in between them.
Sorry I have no pics, and sorry if this is a dumb/often asked question. I'd use the Search feature, but I don't know what to search for.
Thanks