Here are some rings close to what you want, scroll almost to the bottom of the page: http://www.saroftreve.com/hardware/cat-wr.htm Can't help with the buckles though.
Ed, I use this stuff alot at work, but I'm not sure it's what you're looking for. The thinnest it comes is 1/4", and not all that flexible, but....http://www.kingstarboard.com/products/StarBoard.aspx
A funny aside here, Whinewine, I live about 6 miles from Washington's Crossing, and they reenact the crossing every Christmas day. This year the current was too strong, and they used the bridge to cross.