UPDATE: Was able to locate some suitable cable. Thanks!
Looking for a few dozen feet of flat multi-pin cable. It was commonly used for floppy & IDE hard drive cables in decades past. 0.05"(~1.27mm) spacing per wire as I recall, used with 0.1" (~2.54mm) Insulation Displacement Connectors. Anything 3+ wires wide would work.
Sometimes offered in “rainbow” configuration - each wire a different color; colors repeat every 10(?) wires? Rainbow would be great, but any type would work.
Surplus, dusty, unloved, and unwanted preferred (a.k.a. cheap/free), as long as sections are ~5ft+.
What can I offer you in trade? Beer, cookies (of the store-bought variety), pizza?