Posted By:
Dan McCarthyI have a friend from Sewickley, it's in the Pittsburgh area. A quick search turned up this place: http://www.hovisauto.com/. Kaiser Frazer was an automaker; they made some really cool looking cars in the 50's. Based on that and the fact that the Hovis auto site says the company was opened in 1952, I'd say they jersey dates from the early to mid 50's.
Edited to add: My friend said that the colors of Sewickley Academy are red and black, but their mascot is a panther. Freeport, Pennsylvania does have high school teams named the Yellow Jackets, but it is about an hour away.