I'm told the Colorbond product line is a good source for matching the interior leather color in the XFires. Here's a link to the Dark Slate Gray product sold on their website: CLICK. I've found this on Amazon also.

You can also purchase the Dark Slate Gray color in a small bottle from OEM supplier. It's typically listed on eBay. CLICK

There is also a post by Mike-in-Orange regarding the Colorbond product. He used it to make a color change, but can attest to the product's quality. He stated that his seat bolsters were worn and this made the appearance near new by just applying the paint. Here's the link to where his posting starts: CLICK