Fridge Slide Recangular Grommets

I am trying to organise some tie down points on my fridge slide which is made from 50 x 50 x 3 mm angle. I was going to cut some slots and insert some rectangular shaped grommets to protect the tie down straps. I could not find any of these at Clark Rubber, Industrial Rubber Supplies or Universal Engineering Supplies. I did find some doing a web search but they were wholesalers and could not help me. I did ask who retails them here in Perth but no response.
I only assume they are grommets used on the commercial slides. Anyone know where I can buy some ? Thanks Peter