The Director of Practice may entertain a petition for reinstatement from any person disbarred from practice before the Internal Revenue Service or any disqualified appraiser after the expiration of 5 years following such disbarment or disqualification. Reinstatement may not be granted unless the Director of Practice is satisfied that the petitioner, thereafter, is not likely to conduct himself contrary to the regulations in this part, and that granting such reinstatement would not be contrary to the public interest.