No, unfortunately it isn't in Philly... nor Pittsburgh.
But in the heart of good ole' York County, there is a catering company that specializes in pig roasts. I recently found this at an open house I visited in that area and this stuff is more authentic Carlolina-style BBQ than I've ever had in the Carolinas. Very smoky pulled pork served alongside a thin tangy sauce. Literally, not one person who helped themselves at the buffet could restrain themselves from at least a second helping, if not more.
I haven't had a chance yet to call the number to see if they would mail order, but if entertaining any time soon, it may be worth the trip. And if you do go, try to fit in a visit to the Seven Valleys Winery a few miles away.
Seitz Gourmet Cakes & Catering
Seven Valley, PA (actually in Jacobus, PA)
9198 Susquehanna Trail South
Chef: Scott E. Seitz