Only in the solicitation and announcement forum, some people will buy pr6+ domains and then make it a directory, run it a few month as free and then change to paid. Otherwise, there are less than 10 pr6+ free directories.
Hi friend, Here I am new member. Read Your question. visit this site,http://www.vmoptions.com/directory-list.php which provide pr details with url list. may be u will find pr 6 site from that list.