2009 Prius cat stolen

Since the Prius is known as a "super ultra low emissions vehicle," the Amazon converter would do just fine and will not trigger a trouble code.

Super ultra-low emission vehicle - Wikipedia

Many users have had good luck with this converter.

And, here is a comprehensive video of an install.

Also, an aftermarket cat is less likely to be targeted for theft.

 

Have a $125 Amazon cat on my car for almost 2 years now no codes runs fine.
Painted mine bright orange before I put it in in hopes they’ll notice it but doubt that matters but the cool part is the end that attaches to the rear pipe is bigger than the pipe so required a bushing welded on so it’s now twice as thick where they usually sawzall it and will take an extra loud effort to cut this cat off which is awesome.

 

Asked and answered.

This should be a few hundred dollar fix.
If your brother has it done at a muffler shop, or if he's handy with a welder, ask about welding some square stock to the pipe at the cut point.


Easy.
Cheap.
Effective.

 

With credit to Georgina for the orange paint of course lol. It was great idea
As it really stands out. Changed the oil the other day the high temp header paint iused worked great the paint still on it.