Zero-time a number of the LRIP V-22's, add palletized "mini-MALF" fire retardant dispersal systems, an upgraded inlet to deal with ah-filled air, and an ability to hover over a body of water and take on water to mix with dispersant and attach them to the US Forst Service. I can see a diorama of one hovering over a lake with a hoe etending down into teh water from the hatch on the lower fuselage.
Once upon a time, some 60+ years ago, there was a children's book on helicopters which depicted a Ch-46 or CH-47 derivative where it was crossed with a CH-54, yielding a large flying crane with four extended landing gear legs like those of the CH-54.
Cannot really see a single one as being too far fetched. For me the LVTP School Bus is the clear favourite, although with the way the UK appears to be heading the Manchester Police Saxon might be a bit too close to being real world