Edit: posted without enough thought, what I said below is irrelevant. Whoops!
You are probably aware, but ff you have no luck in your search you could get a compatible mtb caliper instead.
https://www.sram.com/globalassets/document-hierarchy/compatibility-map/mtb-and-road-hydraulic-disc-brake-lever-and-caliper-compatibility.pdf
You can use a web archive with that link to get one from the right period too.
@deleted started
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Edit: posted without enough thought, what I said below is irrelevant. Whoops!
You are probably aware, but ff you have no luck in your search you could get a compatible mtb caliper instead.
https://www.sram.com/globalassets/document-hierarchy/compatibility-map/mtb-and-road-hydraulic-disc-brake-lever-and-caliper-compatibility.pdf
You can use a web archive with that link to get one from the right period too.