The only repair I've ever had to do to a sheet metal hilt has been to put it over a ball stake once every year or two and remove the dents. A few minutes' work, at worst. 14 guage will dent less, but will be noticably heavier. I've also seen Kydex or steel cuffs laced onto basket hilts. Basket hilts are made to attach to swords in several ways.
Screw clamps are quick and easy, but can slip off or break.
Wood screws can pull out, bend, and break. Bolts and rivets require a hole drilled through the rattan, weakening it at that point. And they break. The point I'm trying to make is that there really isn't a good way to do this. If your hilt is made for screw clamps, it will have metal tabs top and bottom to clamp to the rattan.