I hope by now that you have already found one, but if not, I too had this problem with my old 96 Blazer and my current 98. When replacing the tank, this damn thing broke. I had a hell of a time finding one. The dealer tried selling me something that had an eletrical connector on it. I ended up going through LMC Truck, Truck Parts and Truck Accessories for Chevy, GMC, Ford and Dodge Trucks from LMCTruck.com
They have it and it was only $20 before shipping.