The Standard Catalog lumps all 681 versions of these photos, issued between 1958 and 1965, into one massive listing. Beckett separates the photos by year and by team, and I found a great resource here with the Phillies checklists for each of the sets from 1958 through 1965. The only thing that threw me off a little is that the images I found on the internet when doing a search for "Jays Publishing Phillies," contain the full team name, listed on the fronts of the photos as "Philadelphia Phillies." These photos omit the city and just list the team name. That being said, I'm still fairly confident these are the 1958 Jays Publishing Phillies photos.
(UPDATE (2/16/12): Please see the first comment below from Matthew, a/k/a 14,000 Phillies, for the correct identification of this set.)
So many, many thanks to my father-in-law for adding these to my collection and here's hoping he continues to clean and find cool Phillies stuff!