I think you are looking for an Anchor Shade TM . http://www.overtons.com/modperl/prod...r=view&i=26845
I actually bought one @ west marine this year and only used it once. It is one of those things you think you will use a lot but you never bother to set it up.
I keep mine in the cabin just in case but as far as I am concerned I wasted $180.
You could check Ebay they might have one.