It really was such a small segment of the population that knew how to communicate this way. I didn't really get "online" until the early 1990s. However, it was still before ISP connections were common. I called local BBSes as opposed to using services like Compuserve or Delphi. Only a few years later, most local BBSes were dead or dying and the internet was exploding.

I haven't found a decent stash of old computer stuff in years. These days its either considered garbage and thrown out or "collectible".

Really, you just need a computer old enough to have a floppy controller on the motherboard. I'm currently using an Athlon XP generation computer for reading floppies though I think controllers were included on motherboards for a while after that. The floppy drives themselves can be found on places like eBay pretty easily. You can get more creative and buy or build a usb interface but that is more expense or more work in my opinion.