Hand made cuffs

I want to order a hand made leg/hand/ankle cuffs with frame style buckle. Any advice?
Material is definitely not natural leather (it expensive, and can be easily damaged).

If someone aeady has a design would be nice.

P.S. why not just buy one? Cheap variants is just decoration, they can't resist any force, spend 30 dollars for one pare of cuffs, nah.

$30 is nothing. You get what you pay for. I've made leather cuffs (they are NOT easily damaged when using the right leather) and that $30 doesn't give much profit. Leather is expensive. Even high quality rubber for cuffs is expensive (and THOSE DO damage easily).

In my opinion, syntetic materials, e.g. nylon, would be better. They need less care, cheaper and less likely would be a bad quality.
Mostly cuffs expensive for no reason, furthemore it's difficult to find good one, I've bought few and they were garbage.
I have friend who could make cuffs, but she need something like blueprint.

Nylon is ok, but can be too flexible. Would need safety grade (like the type in safety belts) for decent rigidity. It's also harder to work with. And not that cheap to make unless it is on an assembly line.

Good cuffs are not expensive for "no reason". You're paying for good materials and the expertise of a craftsman. There are lots of good ones out there. You are just looking for cheapest, by the looks of it, and hoping they end up decent.

Plans for making cuffs are out there, google is your friend 😉