Had to make up another batch of wire loop braze-ons the other day. I mostly use these for running generator wire along rack struts. Much better looking than zip-ties, and so much less of a pain in the butt than running the wires through the struts. (And it keeps things a bit more structurally happy by not drilling relatively big holes in small tubes for the wires to pass through).
Now I wouldn't expect any braze-on manufacturer to produce these. Not really a high ticket item. So yeah, had to make 'em myself. Not a big deal, I got my process all figured out at this point. You're looking at about $0.05 in materials and a grand total of about 5 minutes of work here. Quick, easy, effective. Just how I like it.