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.
ancestry.com is mormon (https://en.wikipedia.org/wiki/Ancestry.com#1983)
wouldn't be surprised if many other such resources also are. for the exact reasons as you explain. these people love "converting" the dead to their religion. they offer much less resistance than the living.