duplicates The Secretary may sell such duplicates under subsection (a) at a price sufficient to cover the costs of such duplicates, including labor, materials, dies, use of machinery, and overhead expenses. (c) Proceeds of sale Amounts received from the sale of duplicate bronze medals under subsection (b) shall be deposited in the United States Mint Public Enterprise Fund. 4. Status of medals (a) National medals Medals struck under this Act are national medals for purposes of chapter 51 of title 31, United States Code. (b) Numismatic items For purposes of section 5134 of title 31, United States Code, all medals struck under this Act shall be considered to be numismatic items. 5. Authorization of appropriations There is authorized to be charged against the United States Mint Public Enterprise Fund, an amount not to exceed $30,000 to pay for the cost of the medal authorized under section 2.