Unknown Piece found in CM2250

[dyno]

Hello, Im replacing the oil cooler on my 2014 Cascadia w/Isx15 and when I was removing the water pipe between the water pump and Egr Cooler I found an unknown piece laying inside the pipe. It looks like a valve spring seat… the truck had 400,000 miles on it when I bought it and it never had any major engine work done to it. It now has 750xxx mile. Im thinking maybe someone dropped it in the engine if they were doing major work to it before my ownership?