After Market Parts
ebay is your best bet
Ebay is ok but try checking with the local city/county/state auctions when the Police cars get sold off. Most of them sell the bumpers separatly.
http://www.mitchsplace.com/crownvicmuscle/cvparts.html for performance. This shit is hard to come by. Push bars and cop stuff go to http://www.used-police-cars.com/
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