Looks like this may be it Glenn, mostly appears to be IBM trying different layouts. Makes sense to me, with how involved they were with the early personal computer market, along with the electronic typewriters.

(and sorry about the thread derail, origins of certain keyboard setups have interested me for a while, mostly due to appreciating the modern Mac setup of modifier keys.)

For Roger's initial question, still not really sure what to suggest. The main issue seems to be full sized function keys. The closest seems to be the Logitech UK offerings.