The floor drain in garage consist of a 9.5" cover that sits into a cast iron ring. The problem I have is that the lip on the ring is rusted away, and can no longer support the cover. By looking at it, the ring was set about a 1/4" below the floor when it was poured covering the ring. Inside the hole runs a plastic corrugated weep tile and sand below the concrete slab. My house was built in 1973. Now my problem is finding a same size and setup as a replacement. Preferably in plastic to eliminate rust. Looking online for such an item turned up nothing. Do they still make such a thing? and where to buy?