spesmilo

The chief point to remember is that 1 _spesmilo_ equals 2 shillings, and

Esperanto Self-Taught with Phonetic Pronunciation William W. Mann

Ten spesmiloj have approximately the value of a five-dollar gold piece, twenty marks, twenty-five francs, one pound sterling, etc. The spesmilo, equivalent to about $0.4875 in the money of the United States and Canada, is the unit commonly used.

A Complete Grammar of Esperanto Ivy Kellerman Reed 1922