The Navy didn't use the UH-1C in grey. They did use them as part of HA(L)-3 Seawolfs in Vietnam, who supported SEALs in the Mekong Delta. They were left in Army OD, since they came from the Army, and had NAVY stenciled on the tailboom in either black or white. Here is a website about them.
Seawolf info.
And an example.
I have built one as a Seawolf bird. It came out looking pretty good. Fireball Modelworks now has a HA(L)-3 Seawolfs decal sheet too. The decals were not around when I made mine. I pieced old NAVY decals together and made the destinctive nose decal myself.
Good luck.
Gino P. Quintiliani - Field Artillery - The KING of BATTLE!!!
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