I found this on Ebay. It's wood but you could possibly remove the wood slats and replace them with something like Trex deck boards or just add Trex boards over the existing wood.

Hi Katinparadise, thank you! I'll check it out Great idea w/trex deck. A little creativity will go a long way.

You're welcome Barbara. Sometimes when what we want is not available we just have to do it ourselves!

Hi Barbara, is there a picture you can post that shows the railing you have? A simple custom solution might be available.