Weber switched to One Touch bowls a long time ago.. The replacement price is more than the price of a new kettle. I suggest you save it for a parts donor..
If it was in better shape, it would be worth a salvage.
But old black 3 wheelers can be found for $20 to $30.
New 18's are only $70.
Thanks for trying to do a rescue.. That one looks to be too far gone to save.
AJ