Cortes - When you said you needed a fuel pump with a vacuum line, I thought you wanted a pump that ran vacuum wipers. Well, what you are are talking about isn't a vacuum line, it is a pressure line. On a SC vehicle like a Kaiser or Studebaker, the carb is in pressurized box. When the SC unit provides boost (even though it is less than 3 psi), it can actually squeeze gas back through the carb and fuel pump and into the tank. So there is a line from the carb box to the top of the fuel pump so the top side of the diaphragm in the fuel pump always has the same pressure as the carb box. Whether you can find it or not, the fuel pump casting on all non SC engines has a pin hole so the top side of the diaphragm is at atmospheric pressure.
Well, I have seen fuel pumps that had cast bosses that were not drilled or tapped. You could try drilling and tapping a regular fuel pump but you would also have to plug the regular vent hole.
Most owners have a known SC fuel rebuilt by some one like Kanter.