Ethically aquired snake skins

Hello everyone!
Though I am not a herp owner at all, I have great respect and love for these animals.
I make traditional and primitive archery equipment, and frequently decorate bows with snake skins I get from road killed snakes.
I am always interested in acquiring skins of exotic or domestic snakes to use in my work, but I do not want to buy skins from snakes that were hunted or trapped.
I am interested in getting raw, untanned, skins if possible or even carcasses - of snakes that died of natural causes only.

I am willing to pay, or trade, if need be.

I would appreciate any help or information you can give.