Everyones' comments are greatly appreciated! The consensus appears to be redial, but I'm not terribly disappointed. I still have the option to return it, and have learned a great deal about the line of watches. Though, I'll probably keep it as my first "mistake," since I think it's quite a handsome one.
Gregoire, since your watch is definitively original, I'm interested in when it was purchased. Thanks to Habitant, I have been able to read over "Girard Perregaux Seahawk an Incomplete History," which--though an excellent little text--doesn't cover much on the watches between the 1957 "Deep Diver" and the redesigned 1989 model. For my own knowledge I'd love to get a better sense of the changing logos. The all caps lettering is quite distinctive.
As a few people have mentioned, the crown is probably too large to be original. Though Sea Hawks from the 40's and 50's were known for their large crowns, this just looks too big, and perhaps more importantly, the crown is very flat at the top rather than rounded. As Hessu pointed out though, it does give it more of a diver feel, something I like now that I've given up concerns of "authenticity" with this particular watch.
I'm afraid I've fallen down a rabbit hole, and have even more questions. My working hypothesis is that it's from the late 40's or 50s, and was then sent in for repairs during the 60's and was redialed and given a new crown, which was too large because the size of the watch had increased from 32mm (as mine is) to 35mm. Does that seem plausible?