I own 6 of this exact chair and have had them for about 2 years. The soft nylon glides under the legs have worn down to the point that the metal is now rubbing on the floor. I cant find replacements anywhere. There are three holes in the metal exactly one inch apart and 1/4" Diameter. The entire original glide is 2 1/" long and about 1/2" wide. Any guidance would be helpful.