I thought about using an inflatable rescue boat or a jet ski in the surf, but this might work too. Mean.
The boat only has to pull the handle and rope through the water you can unwind the spool yourself, or get someone else to do it, if it's not powerful enough to pull line off the reel.
One other thought would be one of those torpedo things guys use to pull their long lines out to sea over here, not sure if they have them in the States, but the motors on those things have 5 pounds of thrust apparently, more than enough to tow the handle through some decent west coast surf.
They look like this...