The spring is fine, it's the plastic that snapped. I'll need to open up the controller to be sure, but it looks like I need to replace the R2 button plastic.L2/R2 spring replacements - Amazon.com: 5 Pairs L2 R2 Trigger Springs Replacement Parts Buttons For PlayStation 4 PS4 Controller EveryOne-Buy: Video Games
Trigger replacement video -
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