Go on ebay....you can find cheaper versions on there. Just search for "wakeboard tower rack". I've seen them as low as $90 on there. And I'm sure they'll work fine for what you want. Most of them are made so that you can pretty much turn the mount do any degree to work on any boat. You'll just need to double check and make sure it will work with the width of the bar on your tower. Also, keep in mind you will need a surf specific rack if you get a surf style board. However, I've found that most skim style boards work better in a wakeboard rack, not a wakesurf rack. Here's a quick link to an ebay auction for an example...if the link works...
http://www.ebay.com/itm/Anodized-Com...MAAOSw3ydVu~z9