No point in getting one, IR composite impacts nowdays are cheap enough to not even worry about and if you treat them halfway decent then they will survive
Found this site online and ordered 100 bucks worth, it's legit thought id throw it out there for anyone who might need hose clamps
http://www.dpciwholesale.com/Hose-Clamps/
what did you rig up for the transmission? centrifugal clutch or what? got any pics of the setup? I've never attempted making something like one of them but I have a 13hp honda motor layin around and some free time kinda sounds fun