I got pretty much the same gear as you:
Crit > Mastery = Haste
The better gear you get, the better Mastery gets because more Agility = More crit = Mastery's worth increases because of amazing Crit synergy.
At ~476 iLvl (pretty high), Mastery is definitely better than Haste, until that point, shoot for Haste.
It's variable, though. If you got lower iLvl than that, but got tons of crit, Mastery might still be the better choice.
Use SimCraft, and of course, take results with a grain of salt.
You should try and go for Crit / Mastery on your gear.