Yes, when it's that thin it'll be tricky too! Perhaps TIG and tempering afterwards would be possible? It looks as though it's failed at the bend, or close to it. Corrosion, or work hardening? Unlikely if its spring steel or similar. Perhaps cutting a new one from any thin steel would do the trick for the amount of use it's likely to have.
There are similar handles available for a few pounds for flight cases.
Here's an example. Perhaps one can be found the right length and any holes adjusted to the relevant fixing dimensions, then fitted by sliding it out of the new handle and into the old grip?
Some of that strapping sounds like a good first experiment! At the end of the day, even if it's not the original formulation, it'll still be a piece of metal supporting the handle which will be better than no metal.