Over the years, there have been a variety of tapes and clear films that people have been using to protect their boats from paddle scuffs and hits.
3M now has a new spray product out that is used to form an invisible mask on the hood of a car to protect it from rock impacts etc.
It appears that it may be the perfect product for our needs. Mask off the area around the section you want to protect. Apply and remove a coat of wax (makes it easier to remove film later), spray on and let dry...
Here is a link to Amazon that describes the product.
3M Paint Defender Spray Film
Just thought I would throw it out there...