I agree with John, BSAs are really solid guns, infact i used to own one and hunt with it. The pattern is great and the barrels are strong. But who might know what would have happened in the trade. The most important part is are you buying it from a gunshop, or is it from a seller himself? About the choke you would definitely need to measure because even if it is not altered, choke can mean full choke, three quarters , half choke etc.But most of the British shotguns are manufactured with three quarters choke. All the best!

Kem