The rotisserie came with 2 brackets that slide/clip onto the rack, this supports the spit. The oven came with a large roaster/broiler set, I have two that I still use. They are large enough to do a 20lb turkey in, and are labeled "Radiant-Wall Spatter Free Broiler Grill" . Anyway, the smaller pan that also serves as the lid, sits between the brackets to catch drippings.
You set the thermostat to Rotisserie, on mine it's indicated by a small triangle, and when the spit is inserted into the motor unit the oven automatically switches to the broiler element. For years we rotisseried with the door open to the broil position, but as of late I'm closing the door, not sure which method works the best. I do have the stove and rotisserie manuals and I can scan parts of them if anyone is interested.
You might not be able to come up with a replacement version of the spit. It is a 5 sided shaft about 1/2" in diameter.
BTW, if you do a lot of broiling play with the broiler setting, it really does make a difference in how your meat cooks.