After years of being left in the sun, the handles on my Wilderness Systems kayak degraded to the point of breaking. No need to throw them out, the fix is quite easy, and just requires a trip to the local climbing shop.
I purchased narrower tubular webbing so that it would fit inside the handle.
First, I just unscrewed the handles with a Phillips screwdriver to take them off of the boat.
Cut the old webbing off and thread the new webbing through. Fold the ends over themselves and melt a hole with a wood burner, soldering iron or something of the like. Then, you can put the screws back through the webbing.
Once everything is back together, you can screw the handles back onto the boat.