This is a new supply, not vintage. I was lucky enough to purchase a lot of wedding laces trims.  This is 1" wide x 5 yards.   It is new being taken directly from the new store roll.  It is  white and polyester,  most likely acetate and maybe nylon.  This retailed for $3.00 per yard a few years ago. 

White Trim 1 inch x 5 yards New Supply Bridal supply