Depends on several things...
Scale...Revell makes a T-2 tanker, released in civil markings as the 'Oil Tanker Glasgow', and as the Mission Capistrano in military guise, in 1/400 scale. It's currently available.
There's also a LARGE T-2 from Bluejacket in 1/192 scale. I have both kits, and obviously, they're night and day in complexity, price and size.
In 1/700 scale, Loose Cannon makes a very nice resin T-2. This might be your best bet for a diorama.
Hope that helps,
Jeff Herne