What is the value of a Manton marked Afghan blunderbuss with British lock and barrel dated 1788?

The value of a Manton marked Afghan blunderbuss with a British lock and barrel dated 1788 can vary significantly based on its condition, provenance, and market demand. Generally, such historical firearms can range from a few thousand to tens of thousands of dollars. Collectors particularly value pieces with unique characteristics, documented history, or in Excellent condition. For an accurate appraisal, consulting a specialist in antique firearms or auction houses that handle historical weapons is recommended.