.125 and .250 clear acrylic is usually available at your local glass shop. The size you need for grips would be basically scraps.
Any tools designed for wood will work with acrylic. Cut and file down to the final shape, and then sand the surface with ever-finer sandpaper until you have a smooth surface, and then fire-polish with a propane torch. This takes some practice, make sure and get extra pieces to practice on! Or just buff with red rouge, but you need a smooth surface before you start polishing.
A tip for drilling acrylic; use a dull bit. A sharp bit will pull the material into it. A dull one will polish as it drills.