It both was and wasn’t easy to send packages from the USSR to the USA in the 1980s.

Okay, the easy part. Russia had been a member of the Universal Postal Union (UPU) ever since the Russian Civil War ended in 1922. The UPU had procedures to allow mail to get to countries that didn’t recognize the USSR. There had never been an official rejection of the UPU’s terms that mail should flow freely throughout the world. Theoretically, all mail should be allowed.

Unofficially, of course, the USSR had propaganda objectives even in peacetime. In the 1970s and 80s, mail inspection and censorship was a concern for many US counterparts, who even took it upon themselves to calculate statistics:

In 1988, 89.3 percent of all letters mailed from the United States to the Soviet Union and vice versa were delivered (the breakdown is 87.9 percent of letters from the US to addressees in the USSR and 90.1 percent of letters from the USSR to addressees in the U.S.). In other words, 10.7 percent of all letters were not delivered. The data we obtained from similar surveys in 1986-87 indicated a non delivery rate of 11.9 percent, and the data for 1985 a non delivery rate of 12.1 percent.

The people most concerned by this were Jewish advocates in the US who wanted to highlight the persecution of Soviet Jews. They would often send “vyzovs,” invitations for Soviet Jews to move to the US or Israel, which were of course distasteful to the USSR censors. In the reverse direction, mail from Soviet Jews (including “Refuseniks”) trying to escape the USSR would be destroyed undelivered, and the USSR postal service would claim ignorance, or falsely claim that the mail was marked Return to Sender on the American side, or other such ploys. Shipments of Bibles and religious literature to the USSR would similarly be destroyed by the Soviets without comment.

So what if, for example, you wanted to send a creepy looking doll in an anonymous package in 1986? Nothing in the international postal treaties would prohibit a Soviet citizen from sending such a package. If the message was not human rights-related, a Soviet censor might well pass it on. Or perhaps the sender of such a package, if he were a police officer in Siberia, had friends who knew how to get around the censors; as long as the mail was postmarked by someone on the Soviet end and arrived at a US Post Office in regular fashion, it would continue on to its destination under UPU rules.

Sources

Robert Johnson, “Service Suspended: U.S. Postal Services in WWI and in Europe in Its Aftermath” Collectors Club Philatelist 89, no. 1 (January-February 2010).

“A History of the Deliberate Interference with the Flow of Mail: The Cases of the Soviet Union and the People's Republic of China” U.S. House of Representatives, 1989

"Soviet Disruption of Mail: Hearing Before the Subcommittee on Postal Operations and Services of the Committee on Post Office and Civil Service," U.S. House of Representatives, March 29, 1988