The barrel patent dates fit a double action; a Model 1891 Single Action should read:Oh, check the SN on the barrel. The 38DA barrel will fit on a 38SA frame, and if someone had repaired it in the past, by putting a DA barrel on it, that would lower value. Make sure the number on the barrel matches the number on the grip.
Sometimes the numbers are split with half on the left side and the other on the right. Also, could you see the numbers on the bottom of the latch and the rear of the cylinder?