Bryan: I've done that, and for MOW cars they're fine. Most of mine will never move anyway, so rusty treads are prototypical. But for cars that do move, metal treads would be nice.
Peteski: I suspect that any company making modern detailed wheels could make them. Recess the rear of the wheel, and make the plastic insulator big enough to include the ribs. Both sides would be insulated, but I suspect that there are more steam-era modelers who'd like the ribbed wheels than would want power pickup in their freight cars!