detent pin for muzzle brake

Does anyone know where I can get one of the pin assemblies to "lock" the muzzle brake? You know what I am talking about, the little spring loaded pin that holds the brake from turning. I feel like a dummy, I just built 2 AMD kits and welded right over the pins while attaching the muzzle attachments and now I wish I had saved them to use on my SAR after the sunset. If anyone has the assembly or knows where to get it, and also how to install it, please let me know. I am sure one of you WECSOG alumni can help me out! :thankyou: