matching stain in an old cabin

[winterh]

I am doing some work to my cottage. The walls are stained knotty pine and over the years have acquired a great patina. There are areas where I need to replace existing boards and i have tried to match with stains and even tried mixing but I just can't get it close. The old pine has such a nice aged look but filling in an area with new pine will really stand out. Does anyone know a way to get the right shade. Matching paint is easy but the paint store tells me matching stain on old boards is tough.