Why don't you contact Dwayne's and see what they would charge you to provide a certificate stating that this was the last roll of Kodachrome ever processed.

Sound's like a good idea to me. As a matter of fact, I have a roll of Kodachrome 25 in the fridge. Maybe I should give them a try relative to the last roll of KM-25.

I'll bet someone has already thought of this!

Denis K