Philadelphia's skyline doesn't have enough Art Deco and quality masonry so...
In no particular order...
1) 111 Westminster (Providence, RI, USA)
npr.org
2) Gulf Tower (Pittsbrgh, PA, USA)
rugbyrealty.com
3) CitySpire Center (New York, NY, USA)
Stephen Wilcox/Flickr
4) Scotia Plaza (Toronto, ON, CA)
skyscraper-en.wikidot.com
5) Gas Company Tower (Los Angeles, CA, USA)
socalgreenrealestateblog.com