I tacked my whole chassis together using old CO2 fire extinguishers.
Ask one of the Nu-swift or chubb type fire guys if they have any spare and tell them why and they may give you as many as you want. They have to take them back to their workshops and decommision and destroy them otherwise which is a pain in the bum for them over giving them away.
1.6 Mazda B6 : Garrett TBO339 : 420cc WRX Injectors : FMIC : Microsquirt V3 : LC-2 Wideband : Toyota COP
Build Started Jan 2013 : OTR Aug 2014 : Build Pictures