typeset wrote:
Is it possible this was a custom ordered keyboard?
Custom ordered in terms of it not being a typical "in stock" keyboard, perhaps, but you have to remember that most of the big manufacturers had hundreds of special characters available for special orders. And there were typeface manufacturers that had 'after-market' catalogues of special type as well. In other words, I don't think this is a one-off machine, but it certainly is not a very common one! For all we know there were many English departments at schools and universities ordering these things, and relatively few have survived - or surfaced. No doubt it's a great find, which is one of the things that makes this forum so much fun for me.