I found a guy within a couple of hours that has AD used parts. What is the going rate of rear fenders, used? How about tailgates?
For a driver or super slick finished truck? If you can work metal and repair rust then fifty bucks should get a decent one. If you want something that is ready for primer and paint then probably at anywhere from $250 to $500. New tailgate runs $175 and if not a smoothie, (no "CHEVROLET" stamped in it), then the hours needed to slick one out around all those letters runs twice the cost of a new one. Check with Joe at Dead Zone, he specializes in used parts for old trucks and knows the price market I'm sure.