The Green Hornets was the 20th SOS (Special Operations Squadron) of the USAF. They flew UH-1Fs and later UH-1Ns. Both were painted in the camo scheme you mention above.
The F model is the same short-bodied Huey as the Academy UH-1C kits, but with a different engine/exhaust set-up. Instead of exiting straight out the rear of the aircraft, the exhaust makes a 90 degree turn and exits out the right side of the fuselage. This was due to the above mentioned use of the same engine as the SH-3. Here is a pic of a UH-1F.
There is no F kit in 1/35; you would have to convert it. Italeri does have one in 1/72.
Later in the war, they switched to the larger and more powerfull UH-1N. It is a twin-engined, long-bodied Huey. The new Dragon reboxed USMC UH-1N is available and has some nice extras. It also comes with the correct weapons for a Vietnam Green Hornets bird, not a late '80s to early '90s USMC helo as it is supposed to depict. The new DML version would be the easiest to make in a large scale.
The Cobra Company set is to convert the older, Panda UH-1N that did not come with weapons into a Green Hornet helo. It also has general parts to update the interior of the Panda, or new/updated Dragon rebox, kit into a better representation of a UH-1N. Neither has a well-detailed interior and is missing many items. Here is a link to a review of the CC set.
About the only (poor) pic of a 20th SOS UH-1N that can be found on the net.
Good luck and show us some pics as it comes along.
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