USAF Missions in Nicaragua Late 1950's

A Zippo collecting friend of mine has come into posession of a lighter commemorating a “USAF Military Mission/Nicaragua” dating from the late 50’s/early 60’s according to what he knows about serial numbers. The only info google has turned up is in conjunction with the Bay of Pigs. The time is certainly right but it seems unlikely that covert ops would have souvenir lighters struck. Any ideas as to the occasion the Zippos memorialize?

The bombing missions flown to overthrow the Guatemalan government in 1954 were flown in and out of Nicaragua.

OK, there’s more:

Link

That is the organization “The United States Air Force Military Mission.” The name used by military assistance teams in other countries. Probably a half-dozen guys. No airplanes were involved (I think).