Hi Bill

,
just a thought....the London 1769 / 1762 may be a retailer's / outfitters mark and the number relates to a pattern or a 'sale' number. There may be more hidden beneath the hilt (such as a company name). British swords with serial numbers tend to be stamped on the spine.... Jim will probably add more on this

.
If the stamping is a retailers mark it suggests that the blade was re-worked ( including the Tang ??) and then re-hilted..... I love these mystery swords
Has the blade distal taper ??
Kind Regards David