https://www.amazon.com/dp/B005GY3P2U/

The d rings i used. I like these, its a small business and the rings are polished with nice welds to make them strong.

https://www.amazon.com/dp/B06VTSF7F9/

Here are the 1 inch buckles. Even though they are plastic, they are quite strong and they typically fail at the latching mechanism and not the cord attachment point.