If you are looking for a case (not a cover) that it very strong and protective for traveling, then I recommend the Case Logic model PRSAZC3 which was originally designed for the Sony PRS-300 reader. I kept my case and it works well with the K4. It is too bulky to use as an everyday case, but it is excellent as a protection case for storing your reader away in your luggage.
Best Buy still lists them, though I've no clue if you could actually get one from them. Here is the
link.
Search for PRSAZC3 on Amazon. I see some listed for $6.
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