HEI cap clip

You can make your own from similar sized spring stock. Something like rewind spring from B&S rotary mower. Bend to match to the one you have, heat bend areas to slightly more than red, use smooth pliers to avoid nicks. When bends are complete, heat treat. Heat to cherry red, all, quench in 30 non-detergent motor oil. To temper, lay spring in molten ladle of lead, let cool. The spring wiil, float, do not immerse. Test see if it works.