Also, I seriously doubt that the expense of a replacement box would be all that of a big deal to Hawking. Not that he’s rich (though I imagine he’s not hurting for money), but among folks who can rub two brain cells together, he’s known as being a genius. After all, he’s holding a position that’s been vacant since Newton roamed the Earth, so if Hawking needed a box and couldn’t come up with the dough to pay for it, not only would you have manufacturers tripping all over themselves to give him one (in exchange for some endorsements, I’m sure), but he could probably call his friends at The Simpsons or David Gilmour and work out a deal to get the money.