Jade G10, not Jade micarta.
Search Gray Micarta in Google. One of the links to a woodworking site had grey/black micarta scales?
You could also get some grey fabric and boat building epoxy (West, System 3, Marine Guard 8000, MAS Low Viscosity epoxy, something with clear color and very very low viscosity, not bondo!!) and make some scales yourself? Cut the fabric, soak it with the mixed epoxy, stack it up and clamp it between some wood boards to let cure. It's messy (ziplock freezer bags and parchment paper help with this), but should produce good scales. The Grey will darken when it is wetted out with epoxy, so a thicker material (quilting backer, or grey denim or canvas, 100% cotton fabric) and a lighter color grey would be your best bet.