19A. Where any person on applying for the probate of a will or letters of administration has estimated the property of the deceased to be of greater value than the same has afterwards proved to be, and has consequently paid too high a court-fee thereon, if, within six months after the value of the property has been ascertained, such person produces the probate or letters to the Chief Revenue-Authority for the local area in which the probate or letters has or have been granted,(a) cancel the stamp on the probate or letters if such stamp has not been already cancelled; (b) substitute another stamp for denoting the court-fee which should have been paid thereon; and (c) make an allowance for the difference between them as in the case of spoiled stamps, or repay the same in money, at his discretion.