See below post.

UPDATE: These chips (besides the “P” chips) have been added to the “Guide” as coming from the now closed J&M Cafe in Seattle.

Now closed, the J&M Cafe was in a John Wayne Movie.

http://www.thechipboard.com/index.cgi/md/read/id/1722117/sbj/fs-seattle-illegal-sample-chip-set-fs/