Also called 'headovers', if that's what you're on about. You can get 'em in all good army surplus stores and Millets etc. Cheap enough. Armed forces use 'em.
Shemaghs aren't bad too. Keep you warm and 'quite' trendy. Available in different colours.
Get a normal scarf, cut it in two and sew each half into a loop. You instantly have two headovers for the price of one!