Convert from firkin [butter, soap] to oka, oke [Turkey]

Unit Definition (firkin [butter, soap])
The firkin [butter, soap] is a traditional unit of weight for butter and soap, equal to 4 stone or 56 pounds (about 25.40 kilograms).

Unit Definition (oka, oke [Turkey])
The oka, oke [Turkey] is a traditional unit of weight in Turkey and throughout the eastern Mediterranean. The oka is approximately 2.8 pounds or 1.28 kilograms, although its size varied somewhat over the large area formerly included in the Turkish empire.