B&H Photo is selling red anodized aluminum body caps for L-mount cameras:
“Designed for L Mount cameras, this Locking Body Cap offers enhanced sensor protection with its locking mechanism, preventing accidental removal during transit. Machined from high-quality aluminum and anodized red for durability and visibility, it complements XLCS Cages and provides nearly indestructible camera protection during transport. The red color makes it easy to locate in your camera case or bag, while also evoking the red record button iconic in filmmaking. The cap has been designed to lock into place regardless of orientation, allowing you to install and remove it with ease.”
Colored anodized aluminum body caps for M-mount cameras are available on eBay and Etsy.