You'll probably find the information on or via these sites:
Bell 47 Helicopter Association
Look under 'FlightSchools and Helicopter Services'
Flying the 47
You'll need to check that the operators offer Instruction and/or SFH. Some operators use them for sightseeing flights only.
Hope you find one. Flying a Bell 47 is a wonderful experience, and there's something special about flying a helicopter which made one of most significant contributions in the history of rotary aviation.
