Here is a note that was on ebay. I like the design on the reverse.
The note is from Guatemala. It says it is a P31...however..

First, a P31 should have a date of 5.1.1955 or 22.2.1956 or 16.1.1957

A P37 is dated 22.1.1958

The note shown has a date of 22.1.1958 (Enero=January)

The holder is labeled wrong.

Ebay item#120232205624

Jeff

Makes you kind of wonder about what you buy sometimes........