Euro car parts do them for £50 (non-genuine). I bought my front bumper from them and was pleased with the quality. I think your looking at £200+ from VW. The respray is about as easy a job can get for a bodyshop so I'd guess £100 to £150.
One thing to think about secondhand is that they all tend to be somewhat rusty, and do you want the only crash protection a Mk2 has to be composed of brown iron filings?