I have the same problem, bought from Robert Dyas (customer support pathetic) tracked down using the Robert Dyas Facebook page in the end to a UK importer. Same story, can not get parts, far eastern company gone out of business, etc.
Funny thing is, yes parts are available in the US! Anyway ordered burner (stainless steel) and new hot plate cover today. Cost Around £88 including shipping and taxes. We paid £199 for it 5 years ago, seems a shame to bin the whole unit for the sake of the burner. Hopefully the stainless steel one will last longer.
Site I used was
http://www.thepartsbiz.com/Tony