Blind “wand” tilt mechanism replacement part(s). The core gear in mine had worn down and shattered at some point, and I switched just that part out - it works great. I haven't tested the full thing in place, and, unless you are using a superior material, I think things could be a little too brittle. Especially the “rod/worm” part.

You can see the exact part that this replaces/replicates here. It's described as:

"Wand Tilt Mechanism with 1/8" Square Hole for Mini Blinds - Hook and Sleeve Stem"

Mini blind tilter for various off brands that use a 1" x 1 1/2" headrail with a 1/8" square shaft.

The overall height is 15/16ths of an inch.