So what's the deal? Which carb is the right one?

There's not going to be a judge with a clipboard subtracting points because your car doesn't have a correctly-stamped carburetor. If it's a choice between those two carbs, here's 24 votes (both hands, both feet, all ten fingers, and all ten toes) for using the NOS Dodge van item, which will run much better than the 'remanufactured' '74-spec carb. As has been explained many times when you've asked, the first-year 1945 carbs were a half-baked mess with a long list of problems eventually fixed in later production, and 'remanufacturing' ruins even a good carb.