I almost hasten to say this Tim, but I have slides of this camo JP, but taken at Odiham in 1970. When I saw it at Thorney Island in June 1969, it was still in the early '60s dayglo and silver scheme.I was there for the International SAR Helicopter Meet. A yellow Whirlwind did a SAR 'rescue' of a pilot from it and here is a photo I took on the day.
It never had an 'M' serial, as simply it was never used for 'maintenance' but for SAR training considering the RAF's SAR school was at Thorney Island during the '50s and '60s.
Keiron mentions my report on the SAR meet in his Post #62 above.
I also have slides of all the helicopters at that meet, including the rare Swedish Navy HKP-1(Vertol 44) and here is my photo of this gorgeous 'banana'
Cheers
Adrian