nastyleather

Here is one company that makes custom clicker dies. There is more out there for sure. http://www.weaverleather.com/Supply/ContractAndServices/CustomDiesAndClicking.aspx You could also try your luck on ebay.

I'm pretty new at this myself and are looking for similar stuff. Right now I use leather to hold the d-ring and that works fine, but I'm looking for other options. What is most suitable comes down to application I guess. also I can recomend this site for more osbscure hardware; http://www.wwlhardware.com/