3/8" polycarbonate is my standard plate of choice. I have yet to "buy" a router table plate. c'mon now I just don't get it. Look in the yellow pages for someone that sells plastics locally - walk in the door and ask if they have any drops or scraps of 3/8 polcarbonate. while you're at it get some 1/8" high density pvc or similar. Tell them what you need it for and they can recommend something suitable they have available. The 1/8" stock is for zero clearance inserts. Cut your plate to size and hole saw the center to the throat diameter of your router. Use a 3/8 rabbet bit set to 1/8 thickness for the inserts. machine the inserts to fit- done. I have 4 plates for 4 different routers. saves me hours of set-up time.
Elvis isn't dead, he just went home Yes, I am a joker - Take it with a grain of salt