A person or public body guilty of an offence under this Act for which no penalty other than by this section is provided shall be liable -
(a) on summary conviction, to a fine not exceeding £1,500 or, at the discretion of the court, to imprisonment for a term not exceeding 12 months, or to both the fine and the imprisonment, or
(b) on conviction on indictment, to a fine not exceeding £500,000 or, at the discretion of the court, to imprisonment for a term not exceeding 5 years, or to both the fine and the imprisonment.