John,
My strong and unreserved recommendation is Railroadbackdrops.com.
These are vinyl. You can get them with or without sticky backing. A bit pricey, but worth every penny. James Adams will work with you to provide what you need and make you happy. Backdrop Warehouse? No, no, and H*** no. Total PITA website, refusal to answer their phones, respond to messages or answer questions. I barely tolerate fools, let alone reward them.
George