The sheaths from Knife Leather Traditions are now just about as 'custom' made as you can ask for.  Dave suggested an expansion in custom options and I don't know of ANYONE offering to customize to this degree.  When you place an order in the store, you will now be asked to select the following options before completing your order.

• Leather Color
• Left or Right hand carry
• Belt Loop width (depending on the width of belt you want it to best fit)

(I sure wish he made leather holsters!!!)