What might a third Queen Elizabeth-class carrier cost?

How much might a third Queen Elizabeth-class aircraft carrier cost?

Roughly three to four billion pounds in this conversational estimate.

The question arises while the audience compares modern purchases with the estimated value of the Gold of Tolosa. The rough figure for another Queen Elizabeth-class carrier is three to four billion pounds. It is an order-of-magnitude comparison rather than a costed procurement proposal. The estimate does not separate construction, design, aircraft, infrastructure, or lifetime operating costs. It should be read as the brief figure offered in the exchange.