Good god, I just found this site: https://helloloom.com/ they want $25 for an unbelievably basic loom that is completely useless.

Understanding Countermarche Looms PDF – The Woolgatherers

I've built, or at least started to build, a countermarche loom model. Made from laser cut 3mm basswood sheets.

Currently having trouble figuring out how to make heddles, and the reed might be a problem but I think I figured out how to build a frame and wrap some transformer wire (20 or 28 awg) around it to make one. I figure an 8 dent, possibly a 12 dent, depending on how easy it is to make the 8. It's just a model / toy, but I want it to actually work. It's also a fun learning project.

The combination of standard and metric parts is boiling my brains, but it's a real world problem.

I guess I really should just use metric for the whole thing, but I think better in inches after working 20 years in that paper factory using inch every day all day.

Dot's countermarch universal tie-up: http://fibre2fabric.blogspot.com/2008/07/universal-tie-up-for-countermarch-loom.html