Fortunately I kept the Case logic case I bought for my 300 when I sold the 300. It is a tad large for the 350, but it will make a great zippered, padded, protective case for travelling. I didn't like the looks of the new 350 leather cover from Sony, not to mention the $35 price, so I bought a 300 Sony leather cover at Best Buy for $10 (liquidation sale), removed the connector spline, and used double-backed tape to secure my 350 inside it.
Too bad Sony is forcing us to improvise so much.