The receiver-mounted 7-pin connector on my 2002 connects to the wiring harness with one of DC's posi-lock connectors - the one with the red tab that has to be lifted to disengage it prior to unplugging it. If that's what yours has, you may have to purchase one at the Dodge dealer since I've never seen that configuration in an RV shop. Who knows, though - it might be worth checking with some trailer hitch installer/dealers.
Rusty