so who pays to design and engineer the folding rotor blades?
and presumably it would also need full marinisation - just as required by the Merlins.
The Chinook is no more marine capable than the Merlin Mk3 - and at least converting that is (or should be) a known quantity
Now if cost is a problem, maybe someone could ask Columbia Helicopters to knock up a quick batch of updated new-build Sea Knights. Columbia now own the construction rights.