Convert from firkin [butter, soap] to candy [India]

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 (candy [India])
The candy [India] is a traditional weight unit of South Asia. The candy was quite variable, generally within the range 500 to 800 pounds (225 to 365 kilograms). In the international cotton trade, the candy was generally equal to exactly 7 (British) hundredweight, which is 784 pounds or 355.62 kilograms.