If it's this one
Rhodesia Medal
£350-450
In December 1979, the CMF was established by the Commonwealth to supervise the implementation of the Lancaster House Agreement between the government of Southern Rhodesia and the guerilla forces of the Patriotic Front. Under the agreement UK authority was restored over its rebellious colony and a ceasefire implemented. A general election followed and independence was achieved by the new Republic of Zimbabwe.
The role of the multi-national force was to keep the peace between 22,000 guerrillas and the Rhodesian forces during the cease-fire run-up to the 1980 elections. The CMF was tasked with monitoring the agreement and resembled a UN observer mission except that its duties were more extensive, it enjoyed municipal backing.
CMFR
If it is then there were 2,500 issued according to
ARRSE . I can't find any other Rhodesia medal in the book.