I;m doing a leather covered buckle class this Sat. at the Dallas Maker Space.
Here is the sample buckle. I made a custom stamp for the class. I don't use those bulky metal inserts from the evil empire, just a buckle back onto an internal leather piece.
It holds up well, gives it some rigidity without being uncomfortable and can be bent to shape easily. Once it's glued in, it holds the shape. Double loop lacing around it.
Cheers!