I think both the pulleys are for your engine but are mix matched for years and accessories. I believe Uncle Bob has you covered with a water pump pulley that will be compatible with your crank pulley.
My crank pulley could be wrong too. That's why I need to find out what is correct for a 73 dart with a 318 with A/C and P/S. I could guess, but I don't want to have a pile of pulleys that don't work for me.