I don't have a V3, but this is a standard MOBI ebook with DRM that should be readable on your V3. You will need to give the bookstore the PID of your V3 before you download the ebook. If you use Windows MobiPocket Reader (undated for the V3) and you have connected the V3 via USB, this should be listed under the Reading Devices icon.
However, note that mobipocket.com is always the most expensive place to buy MOBI ebooks. This one is $7.99 at
Books on Board. Fictionwise is another highly rated site for ebooks.