How can you tell what is the stock piece made of? Please keep in mind that car interiors are a very demanding environment for upholstery with temperatures changing from way-below-freezing to a boiling heat, a challenge irrelevant to home upholstery for example, therefore the materials used need to fulfill more rigorous standards. Vinyl, sometimes referred to as pleather as well, is a synthetic material, which comprises a thin rubbery external layer attached to a textured backing. The external layer is not very durable and under normal operating conditions of the interior of a car will become stiff and brittle, which eventually leads to it peeling away from the backing.
From the engineering standpoint it is therefore even more surprising, how often a leather shift boot you think your car has turns out to be a vinyl one, although the seats are genuine leather and the hood of your car boasts its make to be as exclusive as BMW or Corvette. Even some automotive legends such as the Acura NSX or the Nissan Skyline are subject to this phenomenon.
There are aftermarket companies that work hard to fill that gap, however, so luckily whenever you get fed up with looking at your shift boot once it's better days are over, your choices are not as limited as purchasing an OEM replacement with a rather steep price tag (aren't all OEM replacement items ridden with the price disease?). If you Google for 'leather shift boot' dozens of businesses come up that would be happy to furnish you with a replacement item, this time made with real leather.
Be wary of universal boots sold by the biggest automotive aftermarket companies, however. The one-size-fits-all concept behind those products almost invariably means that you will end up with an item that will look even worse than the stock piece. The material will be better, but the fit will be a scandal, sometimes bad to the point of using lengths of string, visible after the install is completed, to hold the boot to your center console and shift lever. After all, unisex products haven't really ever made it big, have they?
Make sure you go with a boot that's custom made for your car when you go shopping for one. It needs to be cut using a template similar to or identical with the one used by your car's manufacturer. Only that will guarantee that the installation is easy (you can expect to be re-using your stock mounting hardware), and that the end result will be impressive.
And do get a shift boot that's made with genuine leather. You will love the smell of real leather your car interior will gain with the new shift boot.