Your best option for tubing is the plastic style, but make sure to get DOT approved. It is a little heavier and made with air suspension in mind.
You run the schrader valves up front, but I would recommend a small portable in the truck that goes to 120 PSI, just in case you need to add air and aren't by a gas station. Also, maybe a union and some spare line in case of emergencies of a broken or damaged line.
Air Line
Fittings for 1/4" Line
Small portable that goes to 120 PSI, which would be enough to lift the bag if needed, would be around $70.
Hope this info helped and answered your questions.