I’m with Seat Covers Unlimited. We offer a Vinyl (similar to a leather surface), and many other upholstery fabrics for the Mazda 3.

We’ve been in business almost 30 years, and I don’t remember seeing anybody doing an actual Seat Cover in real Leather.

If that is the surface your going after, you might have to get your seats re-upholstered (which won’t be an easily removable seat cover, it will be your permanent seat surface). Your best bet would be to try a local upholstery shop if you decide to go this route. It might be a little pricey though. An online company that does a leather upholstery kit is Katzkin. They are the best of the best when it comes to leather upholstery kits. Good luck!!!