low-cost source for copper tubing?

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Original poster: Gomez Addams <gomezaddams@xxxxxxxxx>

The last time I bought copper tubing for a primary, I got it from
Rayback, a surplus plumbing outfit in Boulder.

This time, I plan to use type K (thicker wall than the more common
Type L) 1/2" tubing, flattened in a rolling machine so I can fit more
turns into a given amount of space.  Unfortunately, Rayback doesn't
stock type K, although they can special order it, but they're
refusing to give me a price over the phone.  I guess they don't want
my business any more.

I need 91 feet, or roughly a 100 ft. coil.  (some places sell it in
100' coils, although 60' coils are more common at the big box
stores.  I'd rather not have to splice it if I can avoid it)

Has anyone found a low-cost source for copper tubing - online,
perhaps?  The prices at the big box stores (Home Depot, Lowes) are
shockingly high.

 - Bill "Gomez" Lemieux