Repair the binding, lose the map?

I am in a quandary. I have a treasured copy of Publii Terentii Afri Comoediae (The plays of Terence) printed and published by John Baskerville in 1772. The book is a fine example of Baskerville’s later design and printing (he died in 1775), the text is laid out generously, printed of course in his own Baskerville types on the characteristic laid paper, smoothed or pressed after printing.
The binding is a contemporary full brown calf with faint traces of a diced or cross-hatched pattern, with gold rules to the front, back, edges and insides of the boards and spine, and blind tooling on front, back and spine. An attractive decorative tool is used between raised bands on the spine.
The leather spine is attached by only one hinge, revealing the paper linings: fragments of a coloured map of the Caribbean. Recently identified as “A New and Correct Map of American Islands, now called the West Indies . . .” by Thomas Kitchin, it was published in the September issue of The London Magazine, 1762.…
The binding is a contemporary full brown calf with faint traces of a diced or cross-hatched pattern, with gold rules to the front, back, edges and insides of the boards and spine, and blind tooling on front, back and spine. An attractive decorative tool is used between raised bands on the spine.
The leather spine is attached by only one hinge, revealing the paper linings: fragments of a coloured map of the Caribbean. Recently identified as “A New and Correct Map of American Islands, now called the West Indies . . .” by Thomas Kitchin, it was published in the September issue of The London Magazine, 1762.…