I just picked up a second copy, and so was easy to compare to my original. It is funny what you can see if you have time (and the right tools). I see indications of a Re-entry in the Numeral Box, and in the "F" on the right side.
Normal Stamp:

Suspect, Re-Entry Stamp:

The numeral box, with the normal one first, followed by the suspected Re-Entry. Note the extra line above the numeral box, plus small indications throughout:


But what is most interesting is the extra line right in the middle of the "F". This may be a guide line, but I am leaning towards a Re-Entry. Normal followed by the suspected Re-Entry:


It almost looks like a shift equal to about one background line. Does anyone else have something similar to show? Thanks for looking.