A: Not on line but I believe some of the stores in the North East sell it by the foot. If not you could by non-jacketed copper refrigeration tube and sleeve it with flexible electrical conduit to achieve the same thing. I believe most stores offer raw copper tube by the foot. The jacket is meant to offer an additional level of containment and to keep the copper from being exposed to things such as concrete; which will initiate corrosion. By running the copper tube through the plastic conduit you achieve the same result and was the preferred method until the development of this product.
A: Some states require that when copper refrigeration tube is used as fuel line from the oil tank to the appliance that it be jacketed as secondary containment in the event the copper tube becomes compromised. In many states this produce is used for that purpose. To be certain of what is required in your area you would want to consult with a local qualified licensed professional or inspector in your area.
A: Sorry but that is an issue of code which varies state to state. To get a definitive answer you would need to ask either a qualified local licensed professional or the code enforcement official in you your area.