Keldor @dylanio21D Shapeways does not currently offer a grey plastic. They have a "metallic plastic" (Alumide) that has a salt & pepper look but this piece is too detailed to print in that material at this time. I've made this model available in just about every material that Shapeways is currently confident will result in a successful print (except for a few absurdly expensive precious metals). I've seen great success with people simply painting "detail" plastic prints.
Sorry, no. Minimates grips are smaller than Lego. If you really want it for Lego you could wrap tape around the grip area until it is thick enough for a good grip. Otherwise it would be too loose or just fall out. If I ever get around to modifying it for Lego I will let you know.