gaskets found in Rad

This morning when inspecting my coolant level I found two small square
gaskets floating under the rad cap. I have a better than average
condition Toyota 3VZE Japanese 4WD Extra Cab with 290K Kilometers. Has
been religously maintained. The gaskets are small 1.5 in by 1.5. Any
ideas where there from and what I should do? I took it to a Canadian
tire and showed them the gaskets. They said the last time the dealer
changed the water pump the old gaskets probaly fell into the rad.
Truck runs perfect.