Yes, those pieces were purchased from ebay or somewhere on those lines and chopped/welded. However, CNC mandrel benders aren't really that rare. I worked for a small ATV racing shop about 5 min from my house that has an Eagle CNC mandrel bender. However, they can only bend a select few diameters of tubing though because the dies are so expensive. I would say they aren't any rarer than a laser, waterjet, or decent CNC machine. Hell, you can pick up a smaller one new for $40k.
I don't see denting the exhaust tube a bit making much of a difference at all in power. The cross sectional area of a b-pipe or PFP exit tube is only about 1/4 the area of a 2.75" exhaust tube.