They're pretty expensive, and they're only a few feet of hose and a couple fittings. Assembling it wouldn't be a problem - just loctite the threads and go. But where do you get the materials?

I'm pretty sure you can get some fittings at a hardware outlet like Home Depot.

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In the correct dosage, violence solves anything.

I looked around at Lowes, and I saw some hose that would probably work, but I couldn't find the fittings.

Bicycle innertubes.

paintball remote? sounds like you are taling about one of those paint grenades.

I think they're just coiled macroline and fittings. You could probably buy a length of it and a couple fittings for less than the assembly. You'd need a second thing (name escapes me) to screw the tank into. You must get hose and fittings that can handle the 900PSI of the compressed air or CO2, so it's advisable to just use available parts.

I would buy one.

The kits are expensive because the remote line is under tank pressure as the regulator is inside the gun.

Welcome to DIY. He doesn't want to pay the "expensive" price for it, that's why he wants to Do it Himself

Thats why HE would buy one numbnut.

Some things are either not practical or foolish.

This is both.