where to buy this what type what to look at ??
Silpak and other companies sell all sorts of urethanes.
Most make a product that is White and Odorless…
Cures in about 3-5 minutes- and in those thin section remains fairly bendable.
You can literally soak the flat cast railing in boiling water, bend it to the curve you want it to follow, and then hold it in that curve under cold water to get it to stay that way.
Look for a plastics or effects supplier in your area and go to their store… they will have sample chips of all the different resins they sell that you can handle and get a feel for how stiff or flexible they are and you can buy accordingly.