Vapor/Charcoal Cannister

if the jeep one has the vacuum purge valve build in it may even be a better option then the one I listed, since that one requires an external purge valve

got a part number/price for the jeep unit?

I don't, I just saw some on eBay a while ago that had been pulled off Wranglers I believe. But My Tech How-To for the Carbon Vapor Canister - International Full Size Jeep Association mentions Standard Motors Part CP3045 as a suitable replacement, with mods. Again, this is for Jeeps, but I'm hoping they would function in a Plymouth.

We've decided to buy more carbon and refill our canister to see if that works.