The wire for this would need to match the ampacity of what you expect. That size wire tends to be pretty thick. The wire equivalent of a 1/8” busbar which handles 200 amps of current is 2/0 to 4/0.
Honestly wish someone sold busbars for different cells, but any for sale I have not seen the one you describe.
You can cut out on cardboard a pattern to drill the busbar. I’m not saying this is the best way to do this at your house, but here is my thread on making and nickel plating bus bars out of copper bar:
I put together a couple of 25 ah 24 Volt 8S Packs and made my own busbars for this. I chose 1/8" X 3/4" 110 Copper bus bars. •https://www.ebay.com/itm/303841271273 These are rated for a little over 200 amps. Way more than these 25 ah cells will push. I'm deciding to learn how to make my own...
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Takes me a half day to make a set of busbars start to finish. Someone mentioned he pounded a copper bar flat with a hammer to make his busbars, so he did not have to wait for the bar to show up. Locally copper pipe was available for me, but the copper flats had been “wiped out” locally from the supplier. Took me 7 days off E-Bay to get my bar.