According to my trustee Jeppesen FlightStar VFR software (another product like NavBox).
Manston to Le2K(Paris-Plage - LFAT) is 50.8Nm direct which is about half an hour in an R44 (110 kts).
Manston to Le Mans (Arnage - LFRM) is 208.4Nm direct which is about 2 hours in an R44 (110kts)