Chef, watch for the splitter that has a little wheel on the top at each side for adjustment. They were built in 8" and 12" wide. When sharp and adjusted right they do a real nice job splitting leather.
The old Osborne twist handle splitter works for sheath sized leather but takes a little more expertise from the person running it. (never try to split more than half the thickness or you will cut thru)
Weaver leather sells a copy of the twist handle. You can find the ones with the wheels around used, just be sure they have enough blade left.
I've got Pauls vidios on my Chrismas list, doubt my wife will get them for me but my hounds always get me things like that. with six hounds I can have a pretty good christmas.