Evalu8,
It does not need a SARTU to teach SAR skills. The RN have managed without such a unit for ever. SAR is a secondary role for all RN RW aircrew and this forms part of the monthly training requirement. The skills required for Vertrep, boat transfers etc are identical. The rest is environmental training which all aircrew do as part of their normal flying.
I am going to sound biased against the RAF but generally they made a meal out of RW training generally taking much longer than the FAA and AAC to get people FL.