Of note, this guy sells a number of parts for 727, 737, and 747. I know how hard jumpseats are to come by, as I've only seen a few. This one could use some re-upholstering, but could be a good project for someone doing a full out sim with jumpseats invested. (seat is located towards the bottom,almost at the end at the time of this writing)
http://www.angelfire.com/il2/aphs/forsale/forsale.html
Jon