I've got quite a bit of Micarta that I got as scrap when I was working. It is all the electrical insulating material that was used on very high voltage equipment. What I have is kraft/phenolic brown. I've used it for various applications but never for stocks/handles. My skills don't lend to that type of work. The stuff I have doesn't look very good anyway. It sure does stink when run across the table saw or when drilled. Whenever I do any of that, I have to put my clothes in the wash.
As Winelover said, it is somewhat rare today, especially in the decorative types. Westinghouse was the original manufacturer, my employer when I first learned about the stuff. I continued to work for the successor company after Westinghouse went under. I retired almost 15 years ago and I don't know what is used as electrical insulation in the large transformers now. Maybe someone still makes the insulating stuff. Have no idea about the decorative Micarta either.