The short answer is "Yes" - there are UK examiners available in Florida - and rest of USA.
However, the charges are levied by the CAA, not by the examiner - so the current answer to your specific question of "How much for a CPL skill test" is the going rate as published by the CAA - so GB£691.
Depending on location, there may be local travel costs (unless the test candidates position the aircraft to the test venue).