Toyota Repair: codes 0420, 0441 and 0446, catalytic, convertor

Question
Hi

I have 1999 corolla. The check engine light came on months ago. I was told by a mechanic that I need to change catalyc converter and charcoal canister also called carbon canister also called vapor canister(are all these names mean the same part?). I called Toyota parts center and I was told that it costs around $245 for catalyc converter and around $900 for charcoal canister. Including labor that is a lot of money to spend on 1999 car with over 220000 miles on it. My questions are - 1) Can I buy the parts from junk yard and use? 2) Can I use other than Toyota brands? I found for less than $100 on line for Catalyic converter. 3) Can I change the Carbon canister myself? Is it difficult? Is any danger or explosion if I try to change it myself? What steps should I follow? I know the Catalyst converter has to be welded so I will let the professionals do that. Plesas include anything else I should know. Thank you very much for your immediate response.

Answer
Have the catalytic convertor replaced by a muffler shop, they have access to a broader scope of parts and tools.
You can probably get a used charcoal canister at a junkyard or even Ebay for alot less than $900, just make sure it came off a low mileage vehicle or else you'll be wasting your time.  Consider checking the Hollander Exchange manual (most junkyards have this) to see what other vehicles have your identical canister.  You can probably change it out yourself if you are confident in your mechanical abilities.  Make sure you don't replumb it incorrectly, label the hoses with masking tape to easily I.D. them.

Hope this helps,
Vince