Looks like the original grates are porcelain coated. No way to duplicate it that I can think of. Seasoning it with oil would probably be the best bet.
I've gone with the Coleman white gas camp stoves. Have two (and three of the older mantle lanterns). Easier to lug around, work great, nice and portable. Parts are still available, but the fuel can get a bit pricey. (Though they make a propane adaptor valve so you can use the commonly available propane cylinders as back-up).
I have them for monsoon emergency use. In case we lose power I can see - and cook - if the electricity is off for any length of time. Plus if the Mrs. and I go camping, attend a community cookout or church picnic (or have to bug out), I can toss one in the van.