Question for Silcraft Sales Pty Ltd

I have a wonderful set of esteele copper based stainless steel saucepans I bought from Myer in 1989 so they have well and truly expired their 10 year guarantee. I have broken the Bakelite circle that goes below the knob when dropping the lid. The knob is still on but was just wondering if you have a replacement for this. THe saucepan size is 20 cm.