I think you would need to check with a vintage restoration company or a salvage place. Maybe somebody like this: Brick Salvage in Rockford IL

Or this: Stockyard Brick in Chicago

It's gonna take some legwork on your part. We can send you links all day, but you'll have to go see the bricks.

Good luck finding it. We tried finding similar style matching brick for an addition we did years back. We ended up painting the brick.

I'd talk to a salvage place locally or some contractors who might remove walls. Your brick might be a local variety.

If you can’t find a matching brick you could close up the window from the exterior with a permanent inset shutter, giving the appearance that it is closed in the space where the window was located. Just a thought….

Can you show us the interior where you are doing this ? I raely like closing off windows so often work around them but I need to see what you are planning.

The brick on your home looks very familiar. I had an all-brick home in Texas built in the late 1980's that was clad in "Old Chicago" brick veneer. The bricks were reclaimed from various warehouse tear downs in Chicagoland. Check with local salvage companies for a match.

This looks like clinker brick, so I would Google that, there are a couple companies that sell typical regional styles of clinker brick.

I would do almost anything rather than lose a window. Maybe we can provide an alternate layout for your interior room.

So i’m not neccesarily closing the window, but rather shortening it to make space for kitchen cabinets underneath.

https://www.historicalbricks.com/products/antique-building-materials/clinker-brick/

https://www.clinkerbricks.com/

https://www.raglandclay.com/clinkers.html