I assume you want a “vertical bar” on the rear sight...
MMC used to offer what you want. But MMC is on shaky ground business-wise, and even if you could contact them, I don't think you want to be giving them your money.
While XS does offer a vertical bar rear sight, it lacks the traditional sight notch, offering more of a subtle wedge-shape.
I Dots use a vertical alignment system, but lack the vertical bar you're looking for.
I suppose, you could buy a plain black sight from AmeriGlo, say, and have a slight vertical "bar" ground into the center of it. Then fill that "bar" with white paint; epoxy or engine paint would be a good choice.
You could then pair your customized rear sight with an appropriate front sight--AmeriGlo could no doubt hook you up!
For a handy guy with access to the right tools, this is completely doable, and shouldn’t cost a fortune!
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