Goodwind is the only place where I would suggest ordering Kitespar. I know multiple people who have found somewhere cheaper, but are very disgruntled when they realize they got what they paid for. Goodwind is the only place I recommend ordering from.
Glaum made a 7' spear out of banshoppe pole, and its so incredibly light... Maybe that would work for your glaive too? I honestly don't know how kitespar would holdup in a glaive. I know we snap the hollow core in blues, and they are only ~30-40 inches, max. The thicker dimensions would obviously help, but I can't speak from experience on the matter. Trial and error time! lol