I too read that bit about all the parts being re-chromed for about Ł300. I recently had four opening ports, oval about 16" x 6", rechromed in London. They made a superb job, but they were nearer to Ł300 EACH (well certainly more than Ł200 each, I try not to remember).
There was more work involved than I had anticipated and while I cannot comment on whether or not I was overcharged, I thought it was worth warning that a serious job might cost serious money. I can't say if I would have had them done if I had known how much it was going to cost when I took them out, but they certainly look superb and probably good for another 30 years.