Quoted from YeOldPinPlayer:This seems like a great opportunity for 3D printing. Scan the broken ramp, fill in the missing part before printing.
The problem with attempting to 3D print a ramp is two-fold: first, the average printer's finished creations always have ridges in/on them from the way it is printed in layers. Second, even if you print it a little thicker and then try to sand out the ridges, the material used is not strong enough to withstand the constant barrage of 80gram metal ball bearings. It will crack.