The cost of the replacement crowns would depend on many things. The exact type of crown and porcelain system used, how difficult the treatment would be to carry out on you, the quality you desire, the level of the aesthetic result you desire,the expertise, experience and skill of both the dentist and the dental technician used to carry out the work, where you have the work done etc… For example if you have the work done by a very experienced and highly regarded cosmetic or specialist dentist in Harley Street and your case is very complex or difficult to manage, then the cost is likely to be more than somewhere outside of London with a younger less experienced dentist working on an easier job, who uses a laboratory of poorer quality.

Removing the old crowns often requires cutting htem off and even if they could be removed intact the gold value is usually not a lot as gold dental crowns are gold alloy, not 100% gold, Maybe a few pounds?

High quality porcelain crowns usually cost upwards of £700 – £2000 in London but this would have to be individually priced for you following a consultation and examination

The best thing for you to do is to decide how good you want the result to be and choose a dentist that fits with your expectations and budget and make an appointmnet to see them. They can look at all your concerns and investigate the reasons behind your sensitivity also

Hope that helps?

Best wishes

Mark