I have seen some crazy priced quick release fir extinguisher mounts being sold recently. Here is a nice piece I saw in my 4 Wheel Parts magazine that is out by Drake. About half the price of other billet style mounts I have seen.
Fire Extinguisher Mounts by Drake Off Road - Fire Extinguisher Holder - Fire Extinguishers & Mounts - Fabrication & Tools - by 4 Wheel Parts
Fire Extinguisher Mounts by Drake Off Road - Fire Extinguisher Holder - Fire Extinguishers & Mounts - Fabrication & Tools - by 4 Wheel Parts