I think you'll find that 1.962 - 1.964 is gonna be the right fit. All 4 of mine interchange perfectly in both my 41 MNBH's. I thought you were measuring the frame all along. I don't think you can get a good measurement from a badly damaged cylinder.
Jeb
PS, if you want to try the 1.963 and it dosen't fit, just send it back. Were I you, my only concern from this point is that the blow didn't open up the cylinder window in the frame. You might try the inside portion of a good caliper to measure from the barrel forcing cone to the recoil shield with the gate open - don't know, never tried it. Good luck.
PPS, worst case, if the frame stretched a few thousandths but all is still fairly tight & square, you can use those cylinder shims. I think they come
.002 - .006 in .001 increments and are almost invisible. Any combination of two shims would get you where you have to be. Then it's just to check cylinder gap. Wheew - I'm done now!