Still very much a 'MAY' but the new EC145/BK117C2s for London will have an option to carry a winch. The first such to be likely used.
Although the option is there there is no public domain timetable for the entry into service of this option.
Historically SAR never did really happen in London [and most other UK police locations] ... a decade ago the police needed to be on hand for a River Thames accident in the early hours [the sinking of Marchioness]. They were not even operating their Bell 222s at that time of day then and such a scenario was not exactly expected. They had to call in the MCA and the military but their arrival was long after all hope had been lost. I can imagine the panic in the control room at Scotland Yard as someone tried to find the right telephone number for the military and MCA options for the first time!
The first Bell 222 for London had a winch on delivery in 1980 but it soon went into the store and never came out.
The only SAR rescue I can recall was when they hovered their 222 alongside the roof of a burning power station and opened the [conventional] door ... they then invited the hapless victim to step across space and into the craft.
The only other UK police SAR's have been a range of helicopters of various forces dunking the skids to drag water borne victims from rivers and the sea - each event causing the CAA to have kittens.