Lot#3329 in this auction "Pennsylvania Committee of Safety" musket is described as having a barrel regimentally marked to the 79th Reg of Foot which was authorized in January 1778.
The 79th sailed for Jamaica in March 1779. They were supposed to have one company on recruiting duty in New York City until 1782 when the entire regiment was sent to New York.
The 79th and the 1st Battalion of the 60th participated in the campaign to seize a Spanish fort on the St John river in Nicaragua.
See my article in Man at Arms Magazine Vol 30, No 5 2008, A Wartime Brown Bess of the 79th Regiment of Foot for detailed info on the 79th.