Pinsider Freeplay40 makes ramps and the visor for Pinbot.
For the plastic piece try posting here:
Do you need just the topper, or the topper and all the electrical set up? Someone was making and selling just the topper. Try posting in the Pinbot club as someone may have that one playfield plastic, and they can point you to the guy that makes the toppers (see post 4463):
If you need the electrical wiring for your pinbot, or you also want to build your own topper, read this: