Here are a few: This one fits the best: Secure the Blessing (http://rahmi.livejournal.com/97723.html)
And this one is good too, but it only has 2 or 3 chapters and is wip: Dream a Little Dream (http://tir-synni.livejournal.com/299066.html)
And this one is a little different. It's the Dean from The End who goes back in time: Following My Footsteps Home (http://masterlist415.livejournal.com/110816.html)
And here are some general back in time fics (http://www.delicious.com/redfoxrose/back-in-time) that don't exactly fit what you're looking for (like they focus on Sam instead or something) but are still good if you want to check them out.
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Secure the Blessing (http://rahmi.livejournal.com/97723.html)
And this one is good too, but it only has 2 or 3 chapters and is wip: Dream a Little Dream (http://tir-synni.livejournal.com/299066.html)
And this one is a little different. It's the Dean from The End who goes back in time: Following My Footsteps Home (http://masterlist415.livejournal.com/110816.html)
And here are some general back in time fics (http://www.delicious.com/redfoxrose/back-in-time) that don't exactly fit what you're looking for (like they focus on Sam instead or something) but are still good if you want to check them out.