First thing you have to decide on is what pressure you are going to run...I'm going to assume you are running a low pressure system 8bar max. I have run similar system using a paintball regulator which plugs directly onto a paintball bottle. The linked regulator is similar to what I have used: http://www.ebay.com/itm/Paintball-Co...0AAOSwg3FUoDEF
Dirt cheap and functional. There are other similar more expensive options such as this http://www.ebay.com/itm/CO2-Paintbal...YAAOSwax5Ys-w-