I purchased a cheap 'kindle 4' cover from ebay, expecting it to be of similar quality to the PU cover I bought from Skindigital (one with elastic straps) but it smells of chemicals and the material wasn't very sturdy. I recommend the Skindigital cover except you cover the decal skin if you have one

On a side note, the ebay kindle 4 covers fit both the Kobo Touch and the Sony PRS T1