You can get leather seat covers from Katzkin. The last time I checked, it was about $800 for DIY installation and a little over a grand with installation. These are not those cheap JC Whitney seat covers that go over what you already have but instead they replace the leather/cloth. You'll need some upholstery skills and tools to do it yourself. I believe they also include matching door panels.
White leather??? Personally, I think you're nutz. I have a hard enough time keeping light beige clean. You might want to start in a junk yard and find some nice leather seats (I'm assuming you have cloth) to install. You can find them on Ebay but unless you live locally to the seller, you'll end up paying as much as the Katzkin covers with shipping.