Don't know if they are or not. Too bad we aren't closer. I have a commercial flat bed end dump that I'd happily deliver them for you. The landscape timbers would rot out surprisingly fast compared to the RR ties. Get a weight on them and see how many your trailer can haul. There may also be someone around looking to make a little and would haul and unload for a reasonable amount.
Some horse people change their horse, they change their tack and discipline, they change their instructor; they never change themselves.