I picked these guys up yesterday. Here is info about the 5 pence: http://www.coinfactswiki.com/wiki/Jamaica_No_Date_(1758)_5_pence Here is info about the 10 Pence: http://www.coinfactswiki.com/wiki/Jamaica_No_Date_(1758)_10_pence
That is some really nice historic coinage! I only know enough to be dangerous when it comes to counter marks on Caribbean coins. As I recall, the GR counter mark indicated "George Rex" after Great Britain took over Jamaica.