@Crankthat
Use an AI image generator. Use the prompt: straight metal chain links, up close, crisp lines, green solid background
Put the results into gimp / photoshop. Add a transparent layer. Set color green to transparent. Save as: chain_texture.jpg
Then go into brightness / contrast. Make it darker till the entire chain is black with a transparent background. Add an all white layer beneath the chain layer. Merge the layers. Then invert colors. Save as: chain_opac.jpg