I maintain all of my Hedley holsters with Renaissance Wax and, if color begins to fade, by stripping off the wax and applying the appropriate color (usually black) of Fiebing Leather Dye.
http://www.restorationproduct.com/
http://www.restorationproduct.com/renwaxinfo.html
http://www.fiebing.com/product.asp?typeID=6
Here's a photograph of one which has been so maintained for the past six years:
(http://i2.photobucket.com/albums/y30/RichardS/hedleyholster-sixyears-1.jpg)