This is reflected in the aftermarket catalytic converter costs. There is often times very little difference in actual construction and performance between parts other than one has been tested to meet CARB and AQMD requirements depending on year and model.
Some applications do have a heavier loading of Platinum, Palladium and Rhodium. Also, Cerium area might be greater. But even if a particular CAT has all of these and has not passed the California tests, it will not be considered "legal" as a replacement.
Most shops I have been to do not check the CAT that closely when I go in for testing. They simply hook the car up and run the test. More than likely, you could get away with installing a good 49 state CAT just as long as it ran clean. Just understand it will not stand up to close scrutiny and may be questioned.
As to cleaning the CAT, there is a plethora of information out there. Some of it is horribly wrong. I am familiar with cleaning cats and have performed the procedure on several applications the latest of which was my Wife's 2007 Dodge. There is a paper done as a graduate thesis from Cyprus university that is the basis for most of the YouTube experts. However, a much more concise doctoral thesis from Sweden extends the work and includes re-aggregation via chlorine reactions. The Pdf can be found here:
http://kth.diva-portal.org/smash/get...070/FULLTEXT01
Other than the re-aggregation, both papers concluded that a weak (0.1 M) concentration of heated aqueous solutions of Oxalic and Nitric acids at 50 deg C and applied in series over an 8 hour period removed over 80% of the plating phosphorus and sulfur plus other metal salts such as tin. The light off and conversion rates could be brought back to effective levels again.
My Wife's Dodge threw a code that showed the CAT had gone out. A visual check showed the upstream O2 sensor had been cross threaded by the service tech at the dealer during an unrelated repair. Since the vehicle was out of dealer warranty but still under emissions warranty (100K miles limit) a spitting match ensued between the three parties ( Dodge, the dealer and me). The legal costs would have exceeded the actual repair value. So I performed the "repair" myself. I re-threaded the damaged boss and replaced both O2 sensors. The CAT was visually carbon laden. The configuration of the CAT built right under the exhaust manifold made it easy to inspect with a bore scope passed through the upstream O2 sensor bung. So, before the vehicle was run, the exhaust down pipe was dropped and a used Mercedes mechanical injector was used to inject fluid into the cat via the sensor bung. It was pressurized using an old pressure painting pot. A gallon of Purple Cleaner ( 7 USD at Walmart) was warmed up and put into the paint pot and dispensed into the CAT to remove carbon. A gallon of warm Oxalic acid mix was next passed through ( 5 dollars, free shipping from Amazon ) followed by a warm Citric acid mix ( 2 dollars local grocery ) finally chased with warm De-ionized water. The exudates were caught in a plastic pan underneath the vehicle to be discarded at our local collection office. The gallon volume and the flow rate of the injector only resulted in about 40 minute pass through times. But it seemed to do the trick.
With the 2 new O2 sensors and the cleaned CAT, the code disappeared and the vehicle passed with pollution levels far below the average for passing vehicles in that year and group, for the strict CARB/AQMD region.
Understand, the use of weak organic acids was due to the desire of the original Cyprus paper to use benign products. Other acids can be used. However, understand that high heat and strong reactive acids can strip the precious catalysts from the substrate rendering the CAT useless. So, follow the procedure as closely as you can and you can be rewarded with an effective CAT again.