The format with which they appear on the net makes them hard/very hard to copy. Contacting may be only option
I'm not sure what the legal issues would be with taking them straight off the net, anyway. It looks like the BBC means free as in beer, not speech. While the copyright on a 16th century map has almost certainly expired, the scanned version of it might be copyrighted (I'm no expert, but I'm sure someone here can tell me whether or not scanned images are copyrightable). The site doesn't seem to say what the copyright status is.
It's probably best to contact them directly.