I've been wearing a modern replica of a US Army Officer's Beltplate from the Civil War era on a black leather belt for years now. It is a typical modern belt buckle that you could use on any 1 3/4" leather belt.

Taking that same concept for a kilt belt, my aim is to go to a civil war reenactor's vendor and get an actual historical replica of a belt and two piece beltplate (as the originals were) to wear with my kilts. The belts will be 2"+ and will make a great kilt belt. #274 on this webpage is an example of what I'm talking about: http://www.jarnaginco.com/catframe.html