Reflective silver Mylar for dozens of uses. Nine meters (approximately) for the price quoted.
Our genuine DuPont Mylar stock is 200mm wide and can come in any length you like up to 6000 meters ;-) This is relatively thin material that was originally used for competition streamers.
It will take a crease so that you can make max perf streamers but it can also be used as parachute material, too. It is great for a release layer when fibreglassing because epoxy or polyester resin just doesn't stick to it.
There's lots more you can do with it. Make a heat reflector or laminate it on your rocket for a real metallic finish. Keep the heat out of your car while it's parked in a field while you launch rockets? Etc etc etc!
If there are some sections that are less than perfect, we add a bit more