A Confederacy of Dunces is on sale on Audible for 4.95.
Beware though, it should go off sale in the next 5 or so hours. I'm a bit late on the message.
I've never done a full audiobook. Feel like I would get restless with my eyes having nothing to do, I guess I could read along? Or just do something else while listening, but that might be hard to pay full attention