I have never tried it but when I googled wok burners (thinking to find a standalone high-output gas hob), I found this article about a wok ring called the "WokMon" on Serious Eats and had to post it here:
A couple months ago I was approached by Glen Lee, an inventor who claimed to have an ingenious new device for cooking in a wok at home. Seemed to me that if it worked the way he promised, it would to revolutionize home wok cooking in the same way that the Baking Steel revolutionized home pizza-making.
I played around with it a lot, measuring, tinkering, reporting a few issues (it's still in development phase and has kinks to work out—luckily Glen has been extremely receptive to feedback), and generally cooking up a storm. I'm happy to report that this thing solves a problem I've been trying to work around for over a decade.
It's called the WokMon, and it's like steroids for your gas burner, helping to concentrate your flames and, more importantly, put them under the center of your wok, where they're supposed to be.
It looks like it does exactly what you need but is way cheaper than buying a specialized heat source and doesn't require more equipment.
Unfortunately, they're not quite in production yet, it seems, though you can pre-order them on their site.
Here's an action photo of the flame it produces off a standard gas stove: