Vintage Eero Saarinen Womb Chair

Vintage Eero Saarinen Womb Chair Mid Century Modern . Having a hard time dating this chair. It's missing one foot glide as seen in picture. No large tears or stains. Does have a few spots that look whitish that i haven't attempted to clean.No tags that I've seen. Please use pictures to aid im description.   Please feel free to ask Any questions I'll do my best! Thanks and have a fabulous day!