When setting up the “plan” for the shop I did a little research on the carbon footprint of a “new” bicycle. The idea was to point out that either buying a good used bike or getting that old dusty thing hanging in the garage tuned up and running would be a whole lot better than buying a shinny new bike (especially one of those cheap things from one of the big-box-stores). Given the choice between buying new bike and not riding that old bike and thus using a car, bus, train, etc. I would certainly tell you to get a new bike from a bike shop. The below article from “Slate” www.slate.com put out some compelling numbers.
“Choose wisely grasshopper.”