Butcher block is a pretty traditional choice and can be DIY-ed

First of all those cabinets are really really pretty!! Love the detailing.
Wood always looks nice with navy. So a deep butcher block is a great option.
Maybe concrete?
Or yes paint to match.
I’d also change out the hardware.
To gold...
keep sharing... we would love to see progress as this project comes together

For the 12 inch wide countertop, I agree that wood painted navy would make it look built in. Since wood is not always available nowadays, you could re-use your laminate countertops, cut to fit. It's possible to paint laminate- look online for instructions and talk to your local paint store for paint recommendations.

I had a dining table, solid cherry that I repurposed for a counter. It already had the beveled edge. You could try a local thrift/consignment/habitat for humanity to see what you could find there.

Another option would be to try a local lumber store. I purchased a 1/2" solid oak board 24" x 72". I added a piece of oak trim to the edges, used poly on it. You can also get other species of wood. Or, 3/4" plywood (birch, oak, cherry veneer?) and add wood trim to the edges and poly.

All of these would be < $100 if DIY :). (assuming less than about 8' of counter)

IMO a 12” counter is pretty useless in a sewing room I find I always need all the counter space i can find in mine so maybe nix the uppers or put them on another wall and butcher block is a good choice .

Those cabinets are lovely! I love navy but wouldn't be overly tempted to paint these. Agree a wood counter would make sense.

Here's a link about vintage kitchens you might find of interest. Pro LB Interiors shared it recently on another thread and there are 2 short articles about counters.

Thank you for the pic. That looks great. And yes, I believe I’m going to have to stick with something fairly thin.

I think a natural walnut-stained piece of wood would look stunning with navy cabinets.

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