You can shop online at places like
http://www.etrailer.com
Use their useful configuration tool by providing the year, make, and model of your toad to find the right parts.
I would also recommend searching Mopar Parts to see if they make a towed vehicle wiring harness. It couples into your vehicles existing connectors, uses 12v power from your coach...and activates all your tail lights including the center brake light. I thinks it's a better option than using a diode kit.
You'll need:
Base plate
Tow Bar
Towed vehicle light wiring
Auxiliary braking and breakaway system
They also make a clamp that is used to eliminate play between your receiver and the tow bar. Another nice accessory to think about is a locking hitch pin..so your tow bar doesn't grow legs and walk off. (Theft prevention)