Just stumbled across this thread over the weekend, and have been a fan of TSB since first really learning about him through Malford Milligan and David Grissom. It has been fun delving into his music the past year or so.
Very likely the same strap for sure, which I've seen in the Dan Was video, as pointed out earlier, but also in several of Jay Curlee's video's which he captured when making his "Rocking the Boat" video (Delbert McClinton's "Sandy Beach Cruise" #12).
After posting that about his strap, I came to learn that Stephen had a bunch of those straps. And I found out from Harvey Levy that that exact model is actually one of Levy's top sellers. Anyway, I'm glad I have it. It and the guitar are a great way for me to remember Stephen. In fact, I think I'll play it tonight.
That strap is a popular one in stores. It's made in black and blue too.
One thing I discovered about it is that it looks great turned backward. I have it on my candy red SG, so it's either the hippie Sunface look or turned around it's black with red binding. I like it both ways, depending on my shirt. lol