Well he would probably have purchased a rifle or smoothbore when he was old enough to earn that kind of money. I'd assume that would be about 16-18 years old at that time and place.
However it was common for very young boys to hunt and shoot, so he may have had a hand-me-down gun too.
What that means is that he could have had any gun used or made during the Revolution and clear up through the declining period of the "Golden age"
I should point out that a gun that is 40-50 year old is not all that old even today.
Many of us have guns from the 1960s and they are in fine shape. True, they are not used as much as guns were in that period, but it's also true that guns were treasured then, and were cared for as well as they could be. There were many old rev-war guns used by southern boys in the Civil war. At that time those guns were about 90 years old and still working. Many if not most had been converted to the "new" cap-lock system by then but not all.
So if he had obtained a gun in Va in around 1800-1810 it would be a flinter, but it could be a rifle or a smoothbore. If he used one that was passed down it could be about anything made in the revolution era, or the years that followed.
If I were you I would go through various books showing guns made around the turn of the century and pick those out that you like. Contact a knowledgeable builder and discuss these things with him, and you will get the gun you want. Also remember that it was ok then to have more than one, and it still is.