This is a very early British trade pistol. I would date it as late 17th century / early 18th century.  It has a 3 screw banana shaped lock with an unbridled pan by T. Gregory.  The Serpent  sideplate is of the earliest design. The stock has had a period repair in front of lock and between the barrel tang and lock .These blend nicely.  The lock mechanism works smoothly and holds on both half and full cock.  A  really rare and  attractive pistol seldom seen for sale. From a time when America was considered the New World!  

Sold