We've got a farm store in the area I live in call Atwoods. It's interesting the things you can find there. I know for a fact I can get compression fittings, barbs, tygon, etc there. And not just your stock fittings. I could get some seriously wonky stuff that just doesn't fit on the water cooling market. You might start looking at places like that for the plumbing portion of your water cooling systems.