Just curious if you need the mirror (glass) only? Or the whole housing? Usually the heated glass can be removed and replaced separately (if available). A picture of what you have would be helpful.
Either way, the place to probably get started is to go to Mopar's website
HERE, and plug in your truck's VIN number. Then search out *mirror* ...and it should tell you what you need based on your truck's actual build. What I usually do once I have the actual mopar part number is do a google search to see who might have the part cheaper. And you can just google "mirror" for your truck's year, too, because another seller might be using an older part number...of the same mirror (part numbers often change). Try searching a few different ways. Purchasing from RockAuto.com, ...Amazon are good sources on expensive items like mirrors.
Also ebay, there might be a used or NOS mirror assembly/glass cheaper, so it pays to check there sometimes. Beware of buying used mirrors from like rust-belt areas. The contacts on the back often become corroded from yrs of salt/elements exposure, and if it works, it may be short lived. From the dry SW would be a better bet.
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