I have a copy of vista here http://www.pdp8online.com/pdp8cgi/os8_html?act=dir;fn=images/os8/dewar-edit… In a search I found this http://vandermark.ch/pdp8/local/Sources/read_dir.php?f=Other/new-22-vista-2… It appears to be the vista editor source. The actual vista source seems to be in the empty at the end if its complete. I haven't tried to build it. Has modules for a couple different terminals.