>> Searching around a little bit it looks like
perhaps a Dallas, TX based
company named "*BITS INCORPORATED*" seems to
have a classified looking
ad for osborne users about a battery pack. It's just a text ad though
so not sure what it looks like.
Google Books shows that ad running from July 5, 1982 - Sep. 13, 1982. As
of the Sep. 20 issue it's marketed as a backup power supply, with no
mention of Osborne.