The RepRapPro design differs from the stock i3.
Anyone with a printer should be able to make the printed parts. There's a section of the forum here specifically for people offering that service. RepRapPro makes the basic STLs available on their github. Sourcing them separately might allow you to find them from someone who will make them of different materials, different colors, or modified designs, or for less than the price difference for the full kit, so it might not be all bad.
