Better photos would be needed to form a confident opinion, but I suspect that it is original. It is earlier than the one that you used for comparison, and IWC used different dial contractors during different periods. In other words, original dials will show variances in the signatures.
Also, if it were a re-dial, it would be a very old one. And frankly, I doubt very much that an effort would have been made to re-create the reference to the store, the name of which is on dial, or the INCA, which of course was an early reference to Incabloc shock absorbers.
Occam's razor leads me to believe that it is likely original, but if you can provide better photos, please do.