Thanks, Jim.
I have a couple of the Athearn ones (L&N) and yeah, they don't look anything like what I saw as a kid. Southern had SIECO ones through my town (as did ICG) which look like the 60' bulkhead flats, but the deck and sides are different. Unfortunately, no one makes the SIECO ones now (I know Walthers did, but retired them).
I have picked up an Atlas General Steel Car pulpwood flat (38' or 40') in GM&O, and will likely pick up a couple more in that and ICG as I can, since I've found documentation that they were used by my railroads and aren't a freelanced car like the Athearn one.
The ones I see for sale now are the ones like Canadian bulkhead flats, but with stakes. I didn't know if they were 50' or larger since Walthers doesn't say, and no shop here has any...I guess because we don't get a lot of pulpwood here. Anyway, I saw some IC marked ones (black with white lettering, so they were post 1980s) outside of Mobile recently, and decided to add a couple to my collection. I'll take your advice, though, and make my own load.
Thanks for the help.