I have a gunite pool that is 20 years old and I need a replacement for the grate for the main drain. The model on the grate says 07017-1751 (white). I searched on the web and it seems that it is no longer manufactured. Would you be able to recommend a replacement for the grate? The dimensions are:

Outside diameter - 7 3/4"

Inside diameter - 6 5/8"

Please let me know

Thank you very much