My DH loves to frisbee golf, and I have made a few bags for him over the past couple years. He always manages to sell them to his friends, so he recently asked me to make him one for himself. As I started I also began looking for something similar to purchase online, and came up with no handmade options. Here is the latest one, I'm working on perfecting this for my shop. The beads are all his idea, to keep score with. I think the future pockets will be higher with no closure or velcro, its tight enough.
I found a great site to purchase wholesale supplies from, its called strapworks.com. They have all kinds of fasteners, straps, everything, in all kinds of sizes and colors. well worth checking out.