People have pulled them without pulling the engine, but it's a bitch and I've only seen it done a couple times. I seriously doubt you'll rebuild them for $200. Check here for rebuild info www.gpopshop.com this place is local to me and good.
You'll need to pull the engine and replace the turbos or have them rebuilt. Price isn't to bad as is, but it won't be cheap to replace/repair the turbos. At 140k when was the 120k service done. I would highly recommend freshening the engine while it is out.
Are you sure it's just the turbos bad. Have someone look the car over carfully for you.
