Searched for local suppliers of the assist hook cord w/o luck found someone from Tuna 360 that found the material atmodel rocketry websites. They use Kevlar as shock cords! 20' of 400# kevlar for under $20 shipped.150#, 400#, 600# and 1000# available
You should have asked I would have hooked you up with a source. It is $ 15.00 for 100 feet of 300# and 500#.
II Chronicles 7:14
if My people who are called by My name will humble themselves, and pray and seek My face, and turn from their wicked ways, then I will hear from heaven, and will forgive their sin and heal their land.