Cast Iron Downspout (Portland)

We are looking for a licensed plumber to replace a cast iron downspout.
The existing downspout has been repaired/replaced with plastic PVC, we would like to replace with cast iron.
The downspout is approximately 14 feet long, and about 3 inches or 3.
5 inches in diameter, there are some elbows at the beginning that lead to a cleanout, we want the plastic replaced with cast iron.
If you are licensed and have the ability to remove the old plastic downspout and replace it with cast iron, please email us with your experience.
Thank you.
Bob