I've tried to find them to no avail. I'm guessing the box sets just aren't made anymore, but I figured it's worth asking in case there's some obscure one out there somewhere.
To clarify, I'm looking for a more recent Linux version. I know the older ones can be found on auction sites and the like.
How curious. Are you doing a play?
You might have to DIY one if you don't want an old one. Certainly there are websites you could upload a PDF to that would print for you.
I think the boxes made sense when they were for sale in a brick n mortar store because they are harder to steal and make the person feel like they are buying something when digital goods weren't such an instinctive idea. I doubt they would be shipped because they are big for no reason and would require a lot of packaging to keep from getting wrecked in transit vs a USB key in a bubble envelope.
To buy linux in a box, you would have to find somewhere near you that is selling it in person. A computer store, a book store. Maybe a campus bookstore? They have a captive audience so sometimes can get away with stuff that doesn't otherwise make business sense.
A play? No, I just saw an old Linux box and wondered if anybody still made them.