I was doing some searching along these lines today and found something that you may be interested in. It is a transparent vinyl repair tape that has a very high rating on Amazon, and is relatively inexpensive. It's called NRS Tear-Aid Patch.
Another approach, though not perfect, is to:
- Cut away the frayed edges
- Get some dark brown upholster's thread
- Get a curved sewing needle
- Sew it together
If I was going to do it, what I would do is remove the seat. Then take off the cover, after learning how with Google searches. Then sew it together from the inside. In fact I did a similar job on my grandson's Celica seat where it had pulled apart on a seam. The only thing is, looking at your picture, I think you might need two small matching pieces to fill the holes. You may be able to cut this from excess fabric under the seat.