Now we only need "Camo Junkie" and the "terrific-trio" from the figures section lands here among the rotor-heads!
To your question: the AH-6J model is hard, if not impossible, to find, but, as pssoff995 suggests, you coud make a conversion starting from one of the MD-500 variants (I did that years ago). Cobra Co's MELB conversion set can help you in this endavour.
The Loach (OH-6) is easier to find since it has been rebxed by Italeri, BUT is a "no-go" since it has four rotor blades and the Y-shaped tail, but if you have the time and will to build the rotorhead and the tail from scratch ...