I think from the initial inquiry posted by O-Gauge CJ, he's not overly picky & is looking for a credible scale hopper that will look at home being pulled by his newly acquired "N&W 4-8-2 K3", even if it only pulled passenger cars. It seems the major 3 rail manufacturers have overlooked the exact prototype for more than one item of rolling stock for the N&W. I think a proper affordable 3 rail caboose is a more significant omission, for what ever the reason, if you ask me. Only expensive brass imports have been available for the Norfolk & Western CF, CG, C2 & CH caboose, except for the Quality Craft CF kit, that I am aware of.
The N&W J was also a passenger engine but it did help out in freight duty & as a helper. I have no doubt that a lot of us run what we like, how we want, & when we want, even if it wasn't prototypical to our favorite road. My point is, that it sounds like CJ wants something that's affordable & looks & runs nice. There are some good suggestions offered here & like many of us, he'll may compromise on the hoppers. He might also feel the same about a caboose, even though it wasn't queried.