For pattern panels most recommend A H Schofield but to be honest any of the pattern panels are not upto scratch, your better contacting someone like Scott Wilson, MEB (Graham l) or FBIVW and buy some cuts off a van being broken.
If you have to use Pattern panels then i would (and did) cut only the bare minimum amount of the bodywork out and use the pattern panel to patch up rather than replace, keep as much OG metal as possible