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This is my favorite slim tpu case from EBay.

Rock .8 mm thin: http://m.ebay.com/itm/161544464382?nav=SEARCH

You can easily find one for less than $10.
 
Might not be the OK thing to do, but i've seen friends with fake Spigen cases from eBay that fit and look great.
I have a genuine one, and only when you put them side by side, you'll notice the difference.

They paid about 9$ I believe.

Once bought a fake (did not know it at the time) Griffin survivor case, which is still on my iPad and looks and performs like a genuine example.

Again, I don't condone buying fake stuff, but they are quite cheap.
 
I received the case from the second link in my original post today, just 3 days after ordering it with free shipping. First impressions are very good -- it fits snugly, buttons are responsive, has an extremely slim profile with a very slight lip and good lens coverage, and the feel is just "leathery" enough to be satisfying.

For only $6.49 I'm very pleased so far. At that price I wouldn't expect it to take much wear and tear, but we'll see. See the eBay link for pictures with the phone in it.

http://www.ebay.com/itm/151473643255?afsrc=1&rmvSB=true
 
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