Here is a link to Catalina Cylinders website. http://www.catalinacylinders.com/paintball.htmlhttp://www.catalinacylinders.com/paintball.html They have a range of sizes. You may find that you wont need 600 g of CO2 depending on your ram size and number of shots required.

You may need room for additional fittings on top of the bottle.

Good luck with it all.