Just get the regular Memory Stick PRO Duo. You do not need the Mark 2 because your camera does not have HD video. Buy a small size, no more than 4GB. That is large enough to hold thousands of images. Purchase your MS from a reputable retailer so you won't end up with a counterfeit.
What is the best/versatile Pro Duo Memory card/stick for for my camera and is there a difference in a memory card/stick? I have also seen Sony brands that are "mark 2". What does this mean?

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