Just theoretically you could replace the converter with a piece of straight pipe and the car should run until the converter came in. Would not pass an emissions test, but who would know?
Unless you could do it yourself, good luck. No licensed shop would touch it, the feds consider doing that to be on par with murder. Well, in blue states it's worse than murder.
CC's are a horribly expensive joke in the big picture. Should be totally a voluntary accessory. Novel thought, huh?
Or you can have a universal cat installed.