CBP was actually pretty helpful on the phone in explaining what I needed to do, and its website has a lot of useful information. This in contrast to our friends in big corporate private enterprise at UPS. The lady there didn't care about my problem. Her main goal seemed to be to get me off the phone. Also my other requests for information from UPS Supply Chain Solutions were more often than not met with puzzled silence.
As a result, I've cancelled my UPS account and will use FedEx for the foreseeable future. UPS won't notice. It only ship occasionally for personal stuff. But I'm not going to do business with them by preference for a while, at least until my fit of pique wears off and I get tired of driving further to drop packages off.
Lesson: Make sure that a foreign seller marks the invoice for Aldens very, very clearly as representing sale of goods made in the USA. Heck you might even get them to cite that section of the tariff code about return of USA made goods.
Probably too much effort for $61, but I'm annoyed.