I have a scanned PDF copy of the November 1960 Phillips Cycle Fitments catalog via
http://www.cyclemuseum.org.uk/ncl/ncl.php
It shows that fork as being number 777 on page 49, one of two available for 28" wheel roadsters.
Interesting that the only other bike I've seen it on is another 28" wheeled Phillips roadster, shown here:
http://oldbikeblog.blogspot.com/2009...-roadster.html
CK