There are a few gennies, and longer 40' ore hoppers on the DLS ... CR, UP, MILW, DMIR ... etc ... And you could reskin them.
Conrail used old 40' coal hoppers, and only filled then 1/4 the way (as iron ore is very heavy) and they ran them till the buckled at the center sill and were swaybellied, with wheel contact against the side chutes, these cars emitted rings of fire