Hmmm, is there any successful civil formerly mil SAR model in use worldwide we could look at / study? I had thought of the RAAF SAR which has been contracted out with S-76 and operated by CHC (with RAAF titles but not roundel) since the rotary wing assets went to the Army and the only SAR a/c in use by the RAAF were UH-1H Hueys IIRC.
The 76 is good in use with INAER - under contract to various SAR agencies in Spain and has served its time with Norrlandsflyg till Aw139 ENTRY . Unfortunately for Hong Kong GFS and its predecessor Auxillaries - the 76 was the wrong ship which is why the EC225 was picked so I am led to believe.
I agree with Harry, that the S-61 in its mil Sea King / Jolly Green / R and civil N has and is the best SAR platform.
Cheers