340 Start Problem

I am the original owner of a 71 340 Duster. It is showroom. 52k miles.
Recently, I have noticed a starting problem, only after the car has been sitting for a week or more. I have a hi-torq starter that turns the motor well. I checked that the carb [new Quick Fuel, but my Carter TQ 9800 did the same] is pumping gas, which it does. I have to pour a small amount of gas into the carb to get it going.
Once it is running and warmed up, it also has a hesitation to get the car rolling, [have to give it extra fuel to get RPM up] but runs strong from that.
Suspect: ?
Distributor [Mopar electronic ignition -30+ yrs old] - new chrome box
Coil- Excel Super Coil -25+ yrs old
Manifold - LD340 [possible small leak]
Head gasket - exhaust seams clean & no oil in radiator