have a search and look through old posts in the relevant classifieds section. Infact, I think threre is a list in the maintinance section of parts required, by dannyp. Lots of info on here....
Anyway, it may be best to buy a mk3 16v as a complete car, and then you should have everything required. It has the potential to be cost effective if you break/scrap/sell the leftovers.