Q, you should make regular trips to thrift stores. They have old computer stuff there all the time. I bought a Commodore 64 for $15 earlier this year for a friend. I've never seen floppy disks at a thrift store, though. Seems like eBay has a lot of them, though.
Here's an auction for 49 disks for 99 cents, plus $8.00 shipping.
Though you could buy a flash drive with 50x the storage and no read/write errors for the same price.