Holding the chrome headlight rim to the body

The bike is a '72 R75/5. After receiving many suggestions, I found the simplest one was the electrical issue that caused the bike to not start. An 8 amp fuse in the headlight bezel caused all of my distress. Of course reassembly resulted in a new problem. The chrome rim was secured to the headlight shell with a tiny spring that came through a hole at the bottom of the chrome rim and attached to a hard metal? cube on the headlight shell. In my effort to free the chrome rim, the the the spring and the cube were lost. A call to Bob's indicated that these two parts are not sold separately and that my best hope is to jury rig a fix. I have a couple of ideas how to do this but none are particularly pleasing. I would welcome suggestions from the members on I might accomplish this.

Thanks
rickt

Maybe a small screw plus a slide-on nutplate inside?
Or, prob'ly not as good, a self-tapping sheet-metal screw?

A well placed small black ziptie?

Kurt