Still call and ask first. Lots of places will list things and say they fit. Then you order without verifying and then find out they don't fit. Then you are stuck with paying return shipping, restocking fees, etc. Then you get pissed and start ranting on social media because you didn't do your homework.
Depends on the offset. Read the wheel size thread and compare specs. Adding if they are close by, take your vehicle there and ask in person. Pretty simple.
Lots of wiring lol.. Seriously, you will need to either integrate the aftermarket stuff with the factory stuff using the correct adapters (I have no clue about that) or, rewire the whole system, but you will still need adapters and wiring diagrams to find out what's what out of the OEM head unit,.
They are all over ebay for like $15 for 2.
http://www.ebay.com/itm/2-New-Uncut-Replacement-Key-Fob-Keyless-Entry-Remote-Transmitter-for-Fobik-Key-/281906312863?fits=Year%3A2009|Make%3ADodge|Model%3AJourney&hash=item41a2ecf69f:g:n2kAAOSwTuJYoXUr&vxp=mtr