Bob let me tell you something most of the time I just buy a old holster but sometimes the one that I like is new and shiny and that's when I break out the fine sand paper and a stiff pot of coffee 
First a new holster has no blmishs and to make it look old some dings,scoffs and dark and light paches if you don't know what I talkin about look at old boots or a saddle that is used to work cows 
Take the sandpaper and work the aeras that may get rubbed,the aeras that you work will be dark when you apply the coffee to the holester remember the more you work the leather and apply coffee the darker the aera will be
When you like what you see work it some more and allow to dry if you still like the it use mnik oil and oil the lether thats what I do and it produces some of the best looking new old holster 
Some of the new holsters are too shiney and that glaze that they use is well let's just say isent right and looks crappy ! Just have fun with it! It is a kick in the pants to do this to some thing new and make it old looking