The owner of the Bike from Singapore wants to keep the bike.
"So it just needs a handlebar," he said when he finally got a look at it. True, the bar was just one more item on the list already compiled. He's really attached to this bike. It's my job to see that he can be securely attached.
After he left I stress-tested the bars to see how close they were to failure.
One side was more oxidized than the other. I hit the drop portion of that side sharply with a hammer. With each blow the weakened upper area split a little more.
After that I used a leverage bar to apply steadier force, because I didn't have a heavy glove to protect me from cuts if the whole thing crumpled into jagged bits. It actually broke pretty cleanly.
If you live in a tropical maritime environment and you have drop handlebars you might want to consider using clear tape so you can see what's going on under there. But I think there's more to this mystery than just that. Like maybe he forgot to mention the time it sank aboard an overloaded ferry boat or something. Wherever you live, check your bars every so often. It can't hurt.