Game time ran out today and I doubt I'll be paying to play again so here is how I managed to get both my t7.5 sets (warrior) in 2 weeks.
A. Clear Naxx/OS/Vault.
B. Go to blizzards main site World of Warcraft Community Site
B1. Go to Account > Character Move > Log in
B2. (Skip) Go to Account > Paid Character Transfer > Log in (See C2.)
C. Usually (Not always) there is a new server or a low pop server Blizzard is allowing you to transfer to for free, if not there's another way don't worry.
C1. If there is, select your character and transfer to it.
C2. If there isn't, you'll have to have a credit card and pay to transfer. (You'll get your money back, don't worry. See B2)
Now I bet you're thinking, why would I want to transfer just to un-save myself?
Answer: You wouldn't. And you don't have to.
After your character has been transferred over you open a ticket and say you accidentally transferred your character over and would like to know if it could be transferred back, he'll hand you off to a specialist and the specialist will tell you you're character will be reset back to what it was before you transferred. You'll also be refunded for the transfer if you paid.
GLHF
I tank 2-3 25 Naxx/OS/Vault a week