So I have been slowly building an Arms set of gear for a few weeks now, i have some fairly decent pieces from Naxx and a few Instance runs. Not the best, but my luck hasn't been that good. Last night I finally got the Saliva Corroded Pike to drop, so I felt it was time to respec to Arms.

I went with this build:
The World of Warcraft Armory

Don't pay attention to my gear please as that's the point of this thread. I tweaked the general Arms Tank build to suit what I felt was best for my play style.
My questions come in when I start trying to gear myself. According to the guides I have read for Arms Specced Warriors the Armor and stat priorities are as follows:
1.Hit rating 264 (At least)
2.Crit Unbuffed 35% (At least)
Can DEF be added into this mix? And if so, then where? Or would DEF gear be an issue of I need to pull it out when I suit up to MT a 5-Man?
I have some other questions about proper gear to use, but I think folks would be grumpy if I linked 38 pieces in my bank, along with my armory listing