So,
My FIL is currently running kegs off a little cartridge-fed CO2 thing. I can buy paintball tanks real cheap for CO2... what's the equipment required to feed one of those into a keg to push beer (no need for force carb). I would just McGuyver a paintball remote line, but I figure that'll easily reach 200PSI and turn the whole thing into a shrapnel shit-show.
Failing that; I guess I need a 5lb'er and a regulator...