How too find and purchase a charcoal canister?
How to replace the charcoal canister? on 1990 Jeep Wrangler
You can probably find the part at either www.parts.com or www.rockauto.com.
Don't bother replacing it. Remove the useless piece of junk (2 screws hold it to the firewall), and cut, and cap the "vacuum" line that feeds it. IT WILL NOT AFFECT YOU'RE EMISSIONS! I have the same jeep as you bro, and I did this a year ago with ABSOLUTELY NO PROBLEMS... My email is email@example.com. Im NO MECHANIC, but I KNOW THIS JEEP.. lol.. F******g YJ's... good luck..