You could get a basic patrol vessel,with a helideck capable of operating a medium sized heli for about E30m. Check out the new Kiwi designs(by the same crowd who designed the P50 class),or the River class RN patrol vessels,which can be fitted with a helideck,if required.
Even the older Castle class of the RN have a helideck,which can land a seaking,with little else.
Whats the point in just getting the bare minimum though?
A Large multirole vessel could have been in a position to assist in the rescue operation,and treat the injured crew without needing to evacuate to a nearby hospital,like in this case,Sligo.