Here is what's written in Jim Elyea's book "Vox amplifiers, the JMI years" :
It all started when Hank and the Drifters made a special trip to Manchester to meet Gene Vincent. While there, Hank was able to check out his mate Joe Brown's echo unit (which Joe didn't like), and decided he had to have one. When next in London, Hank checked in with Jennings and picked up a Vox/Meazzi unit.This probaly happened in march or april 1960, but Hank used the Meazi echo unit for the first time when recording in june 1960 for Apache and Quartermasters' stores.
But before the Italian Meazzi echo units were imported in UK by Jennings, they must have been used in Italy.
The use of single tap echo was quite common in the US, either with a three head tape recorder, or with Ray Butt's "Echosonic" amp with had a built in single tap tape loop echo unit. Less than 70 were made in the mid fifties, it's been used by Chet Atkins, Scotty Moore, Carl Perkins, etc.

Later in 1959 appeared the Echoplex, a separate single tap tape loop echo unit. An Echoplex replica is still being made by Fulltone.

Didier