Dang Derrell, that type of thing looks great.
What's it called? Who made it? Where can I get one?
Making one out of wood as a rail crossing would probably be easier for me than plastic. I would use a really hard wood like walnut or white oak, readily available in 3/4 inch plank, and then run it through a planer to shave it down to 1/4 inch thickness. Then I would trace out the pattern, using one of the Fast Track sections as a guide, and cut the fine angles with an oscillating tool and crescent blade.
I wouldn't try to glue it into the track. I would just set it on the track, and screw it straight down into the plywood base.