Not sure you can find them wider. If so I'd bet they were a specialty item and the "fiscal advantage" would be lost.
The guys have posted several sources for leather you can get in any dimension. I never realized it was that easy to get hold of.
I like this method because you can run to a store in town, make 2 cuts with a knife, tie 3 knots and you've got 3 very cheap, perfectly adequate strops. (of course, I may be biased;))