This is a very open-ended question. I say that because every shop is running their own business. However, for a professional machine shop, doing a job as simple as this, there is no reason it would take longer than a day (assuming they work on it the whole time).
Cost? I would guess around $100 to have it done professionally. If I were you, I would just get the pipes and make it yourself...although I have access to a welder, so...
Hope that helps some.
Jeff