Key Barrell problems :(

[Blep]

So today i went outside to finally get update pictures of my coilover install. When i went to unlock my passenger door to grab my girlfriends camera out. And the entire barrell came off with the key, and something fell to the bottom of my door.

Can you anyone suggest where to best find a replacement? Will i need a new key for it? and is it a hard job to replace? Thanks guys.