1963-D Roosevelt Dime RPM?

I agree. It looks like Machine Doubling. Note how the shape of the lower loop, appears reduced? On other devices in that area, you might see the same thing. But on mintmarks because they were punched into the dies (pre 1990 coins) they can appear taller than the hub devices. When they are taller, the high bounce MD can affect the mintmarks and the over polished devices can be not affected. So you have to determine if the affected areas are reduced in size, whether it was reduced or if it is enlarged showing a spread. If it is showing are spread, then it is a RPM. Look at known RPMs to see if it looks like these listed dies.

I checked Wexler. He only had a 1979D on his site. That's the only one he had. VarietyVista had 6 1963D no match either. One 63D and I know it's not right but I checked other years there. I'm including the 63D&64D pictures (just for comparison.) The top picture is mine.