I had an idea a while back for a way to join a seam in leather without anything but the leather itself. The idea is similar to a zipper. I finally got a chance to try it out on a handle wrap, and was quite happy with how it ended up. Rather than trying to explain it all, I'll let the pictures do most of the talking and answer any questions after.
From experimenting on some scrap, I found that the hole diameter has to be slightly larger than
(edit) the distance between the holes.
Notice in the pic below, I did not
cut out toward the edge on the top and bottom holes along the left side. This keeps it from "unzipping" when it's put together.
You may need some pliers to pull the first and last tabs through the holes, since they are not cut open like the rest.
Once it's started, just alternate tucking the tabs under each other. When you get to the end you might have to use pliers again. You want the first and last tabs to be as wide as you can possibly fit through the holes, since they are basically what hold the whole thing together.
You can tool and/or stain the leather how ever you like. This wrap was a nice snug fit, so I had to use some saddle soap to lube it up enough to slide it onto the widest part of the bow's grip.